RAD-242: add tests for MOC required metadata

[braingram]

RAD-242

This completes the RAD porition of RAD-242.

This PR adds a few unit tests to confirm select L2 metadata and data that is expected to be of a specific format for the MOC. Any changes to the format, structure or requirement of these data and metadata require advance coordination with the MOC and these tests are meant to provide a warning to any schema changes that might require coordination.

This PR is only new unit tests so no changelog was added and no regtests will be run. This also does not require archive review as it makes no schema changes.

Tasks

• Update or add relevant rad tests.
• Update relevant docstrings and / or docs/ page.
• Does this PR change any schema files?
  • Schema changes were discussed at RAD Review Board meeting.
• Does this PR change any API used downstream? (If not, label with no-changelog-entry-needed.)
  • Write news fragment(s) in changes/: echo "changed something" > changes/<PR#>.<changetype>.rst (see below for change types).
  • Start a romancal regression test (https://github.com/spacetelescope/RegressionTests/actions/workflows/romancal.yml) with this branch installed ("git+https://github.com/<fork>/rad@<branch>").
  • Update relevant roman_datamodels utilities and tests.

News fragment change types:

• changes/<PR#>.feature.rst: new feature
• changes/<PR#>.bugfix.rst: fixes an issue
• changes/<PR#>.doc.rst: documentation change
• changes/<PR#>.removal.rst: deprecation or removal of public API
• changes/<PR#>.misc.rst: infrastructure or miscellaneous change

[codecov]

Codecov Report

❌ Patch coverage is 95.91837% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 86.71%. Comparing base (6ab0be9) to head (e49b6f9).
⚠️ Report is 14 commits behind head on main.

Files with missing lines	Patch %	Lines
tests/test_moc_metadata.py	95.91%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #787      +/-   ##
==========================================
+ Coverage   85.87%   86.71%   +0.84%     
==========================================
  Files          14       15       +1     
  Lines        1069     1167      +98     
==========================================
+ Hits          918     1012      +94     
- Misses        151      155       +4     

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