JP-3975: Exclude dhs subarrays from tso3 asn rule

[tapastro]

Partially addresses JP-3975

This PR removes undesirable level 3 associations being generated for long-wavelength NIRCam DHS exposures.

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)
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  • 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

[tapastro]

RTs https://github.com/spacetelescope/RegressionTests/actions/runs/26188072813

Old RTs showed no failures, in part because our DHS pool contained only engineering imaging data and no DHS subarray data. I've updated the pool to use DHS subarray data, new set here: https://github.com/spacetelescope/RegressionTests/actions/runs/26531659627

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.58%. Comparing base (094969c) to head (f5d23fc).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #10567   +/-   ##
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  Coverage   86.58%   86.58%           
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  Files         374      374           
  Lines       40440    40440           
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  Hits        35015    35015           
  Misses       5425     5425           

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[tapastro]

Unnoticed jfrog upload issue, no truth files present... also a refactor to place the update inside the new constraint. Fresh RTs here, which should hopefully pass: https://github.com/spacetelescope/RegressionTests/actions/runs/26578325827

[tapastro]

The refactor of the rule means that the rule will not exclude NRC_TSGRISM data with pupil=CLEAR but not in stripe subarrays, which I believe the past rule was excluding. That said, there are no instances of this in MAST, so I think it may be an inconsequential change.