Move gc.collect to end of step run

[pllim]

Closes #172

Tasks

• update or add relevant tests
• update relevant docstrings and / or docs/ page
• 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 changelog readme for instructions)
  • run regression tests with this branch installed (stpipe@git+https://github.com/pllim/stpipe.git@mv-collect)
    • jwst regression test https://github.com/spacetelescope/RegressionTests/actions/runs/23512447498 (passed)
    • romancal regression test https://github.com/spacetelescope/RegressionTests/actions/runs/23512476825 (passed)

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.35%. Comparing base (3e3765b) to head (cae1281).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #303      +/-   ##
==========================================
- Coverage   95.65%   95.35%   -0.30%     
==========================================
  Files          35       35              
  Lines        3359     3359              
==========================================
- Hits         3213     3203      -10     
- Misses        146      156      +10     

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[braingram]

Thanks. Did this impact memory usage?

Also, would you run jwst and romancal regtests with this change?

[pllim]

Started RTs. Links on OP.

[braingram]

Thanks for running the regtests. They show no memory differences. Is there any benefit to making this change?

[pllim]

Is there any benefit to making this change?

🤷‍♀️

I will have to defer to @melanieclarke or @tapastro 's expertise on this one.