RAD-181: Update guide_star, instrument, and photometry schemas

[PaulHuwe]

Resolves RAD-181

Closes #470

This PR update guide_star, instrument, and photometry schemas.

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

All modified and coverable lines are covered by tests ✅

Project coverage is 95.81%. Comparing base (a32ecf5) to head (466920b).
Report is 29 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #471   +/-   ##
=======================================
  Coverage   95.81%   95.81%           
=======================================
  Files           4        4           
  Lines         215      215           
=======================================
  Hits          206      206           
  Misses          9        9           

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[schlafly]

This all looks fine to me, though of course I defer to Kim on the database side! Note that this also does unit-dropping, which is in Mairan's PR as well, and the plan is to include some unit information in the schema but not to enforce it with the quantity tag. No action needed here, just flagging that the unit-related changes will see churn & conflicts soon.