JP-4265: Unit tests for pathloss

[melanieclarke]

Resolves JP-4265

Add unit tests for pathloss, including optional step parameter user_slit_loc.

Also some minor refactoring for issues noticed while testing:

• update extract_1d test fixtures with a more realistic spectral WCS
• add "SKIPPED" status for multi-slit data if none of the slits were corrected
• add some early returns for correction functions to reduce indentation, for readability
• remove an accidental setting of pathloss_correction_type for IFU: the datamodel for that mode doesn't have that attribute. Log it instead.
• clarify some log messages

Tasks

• If you have a specific reviewer in mind, tag them.
• add a build milestone, i.e. Build 12.0 (use the latest build if not sure)
• Does this PR change user-facing code / API? (if not, label with no-changelog-entry-needed)
  • write news fragment(s) in changes/: echo "changed something" > changes/<PR#>.<changetype>.rst (see changelog readme for instructions)
    • if your change breaks step-level or public API (as defined in the docs), also add a changes/<PR#>.breaking.rst news fragment
  • update or add relevant tests
  • update relevant docstrings and / or docs/ page
  • start a regression test and include a link to the running job (click here for instructions)
    • Do truth files need to be updated ("okified")?
      • after the reviewer has approved these changes, run okify_regtests to update the truth files
• if a JIRA ticket exists, make sure it is resolved properly

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.16%. Comparing base (6cdcc79) to head (6caf391).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #10421      +/-   ##
==========================================
+ Coverage   85.77%   86.16%   +0.39%     
==========================================
  Files         372      372              
  Lines       40081    40091      +10     
==========================================
+ Hits        34380    34545     +165     
+ Misses       5701     5546     -155     

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[melanieclarke]

Regtests:
https://github.com/spacetelescope/RegressionTests/actions/runs/24051281749

All passing.

[stscirij]

This looks great!