pin polars < 0.16

[callumrollo]

No description provided.

[callumrollo]

These tests are failing for slocum, which is odd.

 INFO:pyglider.slocum:./realtime_raw//*.[s|t]bd
Traceback (most recent call last):
  File "/home/runner/work/pyglider/pyglider/tests/example-data/example-slocum/process_deploymentRealTime.py", line 35, in <module>
    outname = slocum.binary_to_timeseries(
  File "/home/runner/work/pyglider/pyglider/pyglider/slocum.py", line 864, in binary_to_timeseries
    time = data.pop(0)
AttributeError: 'tuple' object has no attribute 'pop'
Error: Process completed with exit code 1.

Same failure as #152 so I think that should be resolved first

[jklymak]

recycling to redo tests