fix: typo in ci, variable name python_version

[rubenperezm]

In the previous PR, I've noticed that the coverage wasn't uploaded to Codecov. The problem was that we were using python-version instead of python_version in test workflow and in setup action.

After fixing that, there were some problems while running the workflow with Python 3.8. As this version reached its end of life last year, I excluded it from the matrix and added a more recent version (Python 3.13)

• Fix the typo
• Update the versions tested (from 3.8-3.12 to 3.9-3.13)

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
see 2 files with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[Soap2G]

Hey @rubenperezm, thanks for the changes!
Just left a minor question.