What is claimed is:1. A method for wireless communication at a user equipment (UE), comprising:receiving a preemption monitoring indication in a grant of resources for an uplink transmission, wherein the grant is received on a first downlink control channel, and the preemption monitoring indication indicates whether the uplink transmission is permitted to be preempted by a preemption indication received on a second downlink control channel and wherein the preemption monitoring indication is indicative of a priority associated with the uplink transmission;monitoring the second downlink control channel for the preemption indication; anddetermining, based at least in part on the preemption monitoring indication and a result of the monitoring, whether to transmit the uplink transmission in accordance with the grant of resources.2. The method of claim 1, further comprising:receiving radio resource control (RRC) signaling that configures the UE to monitor the first downlink control channel for the preemption monitoring indication.3. The method of claim 1, further comprising:monitoring the second downlink control channel for the preemption indication based at least in part on the preemption monitoring indication indicating that the UE is to monitor the second downlink control channel for the preemption indication, wherein the uplink transmission is allowed to be preempted by another transmission.4. The method of claim 1, further comprising:avoiding monitoring the second downlink control channel for the preemption indication based at least in part on the preemption monitoring indication indicating that the UE is not to monitor the second downlink control channel for the preemption indication, wherein the uplink transmission is not allowed to be preempted by another transmission.5. The method of claim 1, wherein the preemption monitoring indication is based at least in part on channel conditions or traffic conditions, an amount of downlink control information (DCI) received by the UE and a decoding budget at the UE, or a combination thereof.6. The method of claim 1, wherein the preemption monitoring indication comprises a one-bit field in downlink control information (DCI) received in the first downlink control channel.7. The method of claim 1, wherein the uplink transmission comprises a mobile broadband (MBB) transmission and another transmission associated with the preemption indication that comprises a low latency transmission.8. The method of claim 1, wherein the grant comprises a semi-persistent scheduling (SPS) grant scheduling a sequence of transmissions, and the preemption monitoring indication indicates whether one or more of the sequence of transmissions may be preempted by the preemption indication.9. A method for wireless communication at a base station, comprising:identifying an uplink transmission from a user equipment (UE) to be scheduled;determining whether to include a preemption monitoring indication in a grant of resources for the uplink transmission based at least in part on whether the uplink transmission is allowed to be preempted by another transmission;transmitting radio resource control (RRC) signaling that configures the UE to monitor a first downlink control channel for the preemption monitoring indication, wherein the preemption monitoring indication is indicative of a priority associated with the uplink transmission; andtransmitting the grant of resources for the uplink transmission on the first downlink control channel, the grant including the preemption monitoring indication indicating whether the uplink transmission is permitted to be preempted by a preemption indication transmitted on a second downlink control channel based at least in part on a result of the determination.10. The method of claim 9, further comprising:identifying the other transmission, which is to be scheduled on resources allocated for the uplink transmission; andtransmitting the preemption indication in the second downlink control channel indicating that the uplink transmission is to be preempted based at least in part on the preemption monitoring indication indicating that the uplink transmission may be preempted.11. The method of claim 9, wherein determining whether to include the preemption monitoring indication in the grant comprises:determining whether to include the preemption monitoring indication based at least in part on channel conditions or traffic conditions, an amount of downlink control information (DCI) transmitted to the UE and a decoding budget at the UE, or a combination thereof.12. The method of claim 9, wherein the preemption monitoring indication comprises a one-bit field in downlink control information (DCI) transmitted in the first downlink control channel.13. The method of claim 9, wherein the uplink transmission comprises a mobile broadband (MBB) transmission and the other transmission comprises a low latency transmission.14. The method of claim 9, wherein the grant comprises a semi-persistent scheduling (SPS) grant scheduling a sequence of transmissions, and the preemption monitoring indication indicates whether one or more of the sequence of transmissions may be preempted by the preemption indication.15. An apparatus for wireless communication at a user equipment (UE), comprising: a processor, memory in electronic communication with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to:receive a preemption monitoring indication in a grant of resources for an uplink transmission, wherein the grant is received on a first downlink control channel, and the preemption monitoring indication indicates whether the uplink transmission is permitted to be preempted by a preemption indication received on a second downlink control channel and wherein the preemption monitoring indication is indicative of a priority associated with the uplink transmission;monitor the second downlink control channel for the preemption indication; anddetermine, based at least in part on the preemption monitoring indication and a result of the monitoring, whether to transmit the uplink transmission in accordance with the grant of resources.16. The apparatus of claim 15, wherein the instructions are further executable by the processor to cause the apparatus to:receive radio resource control (RRC) signaling that configures the UE to monitor the first downlink control channel for the preemption monitoring indication.17. The apparatus of claim 15, wherein the instructions are further executable by the processor to cause the apparatus to:monitor the second downlink control channel for the preemption indication based at least in part on the preemption monitoring indication indicating that the UE is to monitor the second downlink control channel for the preemption indication, wherein the uplink transmission is allowed to be preempted by another transmission.18. The apparatus of claim 15, wherein the instructions are further executable by the processor to cause the apparatus to:avoid monitoring the second downlink control channel for the preemption indication based at least in part on the preemption monitoring indication indicating that the UE is not to monitor the second downlink control channel for the preemption indication, wherein the uplink transmission is not allowed to be preempted by another transmission.19. The apparatus of claim 15, wherein the preemption monitoring indication is based at least in part on channel conditions or traffic conditions, an amount of downlink control information (DCI) received by the UE and a decoding budget at the UE, or a combination thereof.20. The apparatus of claim 15, wherein the preemption monitoring indication comprises a one-bit field in downlink control information (DCI) received in the first downlink control channel.21. The apparatus of claim 15, wherein the uplink transmission comprises a mobile broadband (MBB) transmission and another transmission associated with the preemption indication that comprises a low latency transmission.22. The apparatus of claim 15, wherein the grant comprises a semi-persistent scheduling (SPS) grant scheduling a sequence of transmissions, and the preemption monitoring indication indicates whether one or more of the sequence of transmissions may be preempted by the preemption indication.23. An apparatus for wireless communication at a base station, comprising: a processor, memory in electronic communication with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to:identify an uplink transmission from a user equipment (UE) to be scheduled;determine whether to include a preemption monitoring indication in a grant of resources for the uplink transmission based at least in part on whether the uplink transmission is allowed to be preempted by another transmission;transmit radio resource control (RRC) signaling that configures the UE to monitor a first downlink control channel for the preemption monitoring indication, wherein the preemption monitoring indication is indicative of a priority associated with the uplink transmission; andtransmit the grant of resources for the uplink transmission on the first downlink control channel, the grant including the preemption monitoring indication indicating whether the uplink transmission is permitted to be preempted by a preemption indication transmitted on a second downlink control channel based at least in part on a result of the determination.24. The apparatus of claim 23, wherein the instructions are further executable by the processor to cause the apparatus to:identify the other transmission, which is to be scheduled on resources allocated for the uplink transmission; andtransmit the preemption indication in the second downlink control channel indicating that the uplink transmission is to be preempted based at least in part on the preemption monitoring indication indicating that the uplink transmission may be preempted.25. The apparatus of claim 23, wherein the instructions to determine whether to configure the UE to monitor for the preemption indication are executable by the processor to cause the apparatus to:determine whether to configure the UE to monitor for the preemption indication based at least in part on channel conditions or traffic conditions, an amount of downlink control information (DCI) transmitted to the UE and a decoding budget at the UE, or a combination thereof.26. The apparatus of claim 23, wherein the preemption monitoring indication comprises a one-bit field in downlink control information (DCI) transmitted in the first downlink control channel.27. The apparatus of claim 23, wherein the uplink transmission comprises a mobile broadband (MBB) transmission and the other transmission comprises a low latency transmission.28. The apparatus of claim 23, wherein the grant comprises a semi-persistent scheduling (SPS) grant scheduling a sequence of transmissions, and the preemption monitoring indication indicates whether the UE is to monitor the second downlink control channel for preemption indications for the sequence of transmissions.