Remove all hints of roman_datamodels units

[WilliamJamieson]

This PR makes the necessary changes to roman_datamodels to support spacetelescope/rad#248.

Checklist

• Added entry in CHANGES.rst under the corresponding subsection
• updated relevant tests
• updated relevant documentation
• Passed romancal regression testing on Jenkins / PLWishMaster. Link: https://plwishmaster.stsci.edu:8081/job/RT/job/romancal/XXX/

[codecov]

Codecov Report

Patch coverage: 100.00% and project coverage change: -0.11 ⚠️

Comparison is base (ae1caff) 96.73% compared to head (2536ea3) 96.62%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #172      +/-   ##
==========================================
- Coverage   96.73%   96.62%   -0.11%     
==========================================
  Files           9        8       -1     
  Lines        1101     1068      -33     
==========================================
- Hits         1065     1032      -33     
  Misses         36       36              

Impacted Files	Coverage Δ
tests/test_stnode.py	100.00% <100.00%> (ø)

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[WilliamJamieson]

The CI failures seem to be a github issue not a test failure. It seems like the action run was terminated in the middle by some GitHub error. GitHub has been experiencing CI issues for the past few days.

[PaulHuwe]

LGTM - I have updated my L3 PRs to match this.

[WilliamJamieson]

Close/reopen to trigger CI that did not run due to GitHub system issues today.

[WilliamJamieson]

Test failures will be fixed by #174.