DOC: (Follow-up to PR #5325) Add missing docstrings and update CHANGELOG

[ParthUppal523]

Fixes #5317
This PR is a follow-up to my previous merged PR #5325. I realized that the changes made to select_atoms() docstrings in groups.py and package/CHANGELOG were accidentally omitted.

Changes made in this Pull Request:

• Add docstrings for all keyword in select_atoms()
• Update package/CHANGELOG

LLM / AI generated code disclosure

LLMs or other AI-powered tools (beyond simple IDE use cases) were used in this contribution: no

PR Checklist

• Issue raised/referenced?
• Tests updated/added? (N/A)
• Documentation updated/added?
• package/CHANGELOG file updated?
• Is your name in package/AUTHORS? (If it is not, add it!)
• LLM/AI disclosure was updated.

Developers Certificate of Origin

I certify that I can submit this code contribution as described in the Developer Certificate of Origin, under the MDAnalysis LICENSE.

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📚 Documentation preview 📚: https://mdanalysis--5331.org.readthedocs.build/en/5331/

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.83%. Comparing base (9f6d169) to head (a7bddb3).

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #5331   +/-   ##
========================================
  Coverage    93.83%   93.83%           
========================================
  Files          182      182           
  Lines        22492    22492           
  Branches      3199     3199           
========================================
  Hits         21106    21106           
  Misses         924      924           
  Partials       462      462           

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[ParthUppal523]

@BradyAJohnston , request you to review these changes. This is a follow-up PR to PR #5325 as I realized the docstring changes made in select_atoms() in groups.py and package/CHANGELOG were accidentally omitted at my end.

[BradyAJohnston]

The linter is currently failing - you'll need to lint with black 24

If you have uv you can use this:

uvx black~=24.0 package/

[ParthUppal523]

Sure @BradyAJohnston , I have reformatted using black 24 as advised.

Also based on our discussion in PR #5325, I have provided a fix for the First Time Contributor Greeting check which was failing for a few PRs via #5332.