[python] Conditionally apply ContextManager cleanup logic

[XanthosXanthopoulos]

Issue and/or context: SOMA groups are closing their members when running outside of ContextManager when they go out of scope while their member are still being accessed

Changes:
This PR changes the cleanup of members of groups:

• When running under a ContextManager the behavior is unchanged
• When not running under a context manager when a group goes out of scope its members are not being closed unless there is no reference to them

Notes for Reviewer:

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.38%. Comparing base (4de5c73) to head (6d0ae22).
⚠️ Report is 5 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4426      +/-   ##
==========================================
+ Coverage   84.33%   88.38%   +4.05%     
==========================================
  Files         151       68      -83     
  Lines       22004     7671   -14333     
  Branches       13        0      -13     
==========================================
- Hits        18557     6780   -11777     
+ Misses       3447      891    -2556     

Flag	Coverage Δ
python	88.38% <100.00%> (-0.01%)	⬇️
r	?

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
python_api	88.38% <100.00%> (-0.01%)	⬇️
libtiledbsoma	∅ <ø> (∅)

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[jp-dark]

This needs tests for the intended behavior.

[jp-dark]

This test would be cleaner using fresh objects instead of the pbmc3k. That dataset should only really be used if you need "real" data for the test.