remove python 3.9

[filintod]

Description

Python 3.9 is not supported anymore https://devguide.python.org/versions/#unsupported-versions

Issue reference

We strive to have all PR being opened based on an issue, where the problem or feature have been discussed prior to implementation.

Please reference the issue this PR will close: #[issue number]

Checklist

Please make sure you've completed the relevant tasks for this PR, out of the following list:

• Code compiles correctly
• Created/updated tests
• Extended the documentation

[acroca]

Should we also add 3.14 in this PR and close #847?

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 87.13%. Comparing base (bffb749) to head (c2fe642).
⚠️ Report is 48 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #860      +/-   ##
==========================================
+ Coverage   86.63%   87.13%   +0.50%     
==========================================
  Files          84       93       +9     
  Lines        4473     6163    +1690     
==========================================
+ Hits         3875     5370    +1495     
- Misses        598      793     +195     

☔ 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.