add downstream testing of roman_datamodels

[zacharyburnett]

This PR adds roman_datamodels downstream tests to the CI

Checklist

• Schema changes discussed at RAD Review Board meeting
• Added entry in CHANGES.rst under the corresponding subsection
• Updated relevant roman_datamodels utilities and tests
• Passed romancal regression testing on Jenkins / PLWishMaster. Link: https://plwishmaster.stsci.edu:8081/job/RT/job/romancal/XXX/

[codecov]

Codecov Report

Patch and project coverage have no change.

Comparison is base (0898a87) 93.54% compared to head (58d1dd7) 93.54%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #263   +/-   ##
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  Coverage   93.54%   93.54%           
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  Files           4        4           
  Lines         124      124           
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  Hits          116      116           
  Misses          8        8           

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[zacharyburnett]

the roman_datamodels tests need data files; a possible solution could be adding instructions to clone roman_datamodels to the project directory in the toxenv

[braingram]

If possible (and when available) it would be great to revive this PR.

Cloning roman_datamodels sounds like a good work-around. asdf does this for it's roman_datamodels downstream tests.