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 

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

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

[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! 😸