Issue with pysmurf zero_biases wait functionality

The beginning of a satp1 schedule failed with the error because the zero_biases is not actually waiting for set_biases to finish.

2024-01-11T22:29:36+0000 start called for uxm_relock
2024-01-11T22:29:36+0000 uxm_relock:97 Status is now "starting".
2024-01-11T22:29:36+0000 uxm_relock:97 Operation failed: set_biases is running.
2024-01-11T22:29:36+0000 uxm_relock:97 Status is now "done".
2024-01-11T22:29:36+0000 set_biases:96 Finished setting biases to 0
2024-01-11T22:29:36+0000 set_biases:96 Status is now "done".

Zero biases is implemented to call the set_biases tasks and wait to finish like this:
https://github.com/simonsobs/socs/blob/be59fa40bdd2565da61562b627d7021c476ae427/socs/agents/pysmurf_controller/agent.py#L903-L916

However now I'm not actually sure if the wait function will wait if running in a blocking-thread, since it is a generator w/ inline callbacks, meant to run in the main thread. The simplest fix is that this should probably just be a completely separate task and acquire the lock / zero the TES biases itself instead of passing params to set_biases

Start in socs/agents/pysmurf_controller/agent.py at the referenced zero_biases implementation around lines 903-916. Reproduce the satp1 or uxm_relock sequence and inspect how set_biases, wait, generators, and blocking threads interact. Done means zero_biases does not let the following operation start until setting biases has actually finished.