fix(python): output a warning for .venv activation errors

[mwbrooks]

Changelog

Output a warning instead of an error when activating the Python virtual environment (.venv/) fails.

Summary

This pull request updates the Python virtual environment (.venv/) activation issues to be output as warnings.

Related to feedback: #347 (comment)

Requirements

• I've read and understood the Contributing Guidelines and have done my best effort to follow them.
• I've read and agree to the Code of Conduct.

[codecov]

Codecov Report

❌ Patch coverage is 0% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 65.22%. Comparing base (017f8d3) to head (b6013a4).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
internal/shared/clients.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #368      +/-   ##
==========================================
- Coverage   65.25%   65.22%   -0.03%     
==========================================
  Files         216      216              
  Lines       17991    17991              
==========================================
- Hits        11740    11735       -5     
- Misses       5160     5163       +3     
- Partials     1091     1093       +2     

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[zimeg]

⚠️ @mwbrooks Praise once more! Making problems known makes these quick to be addressed in troubleshooting! Amazing change!

[mwbrooks]

@zimeg Thanks for the review! 🙇🏻 Lots of credit goes to you for suggesting the change! 😸