Maintanance/GitHub tests for python 3.10

[joda9]

Description

Changed the github workflow to python versions 3.9 and 3.10. The Tests for python 3.8 are not longer provided

Please delete options that are not relevant.

• New feature (non-breaking change which adds functionality)

Checklist:

• New and adjusted code is formatted using the pre-commit hooks
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• The Read the Docs documentation is compiling correctly
• If new packages are needed, I added them the setup.py, and if needed the rtd_requirements.txt, the eDisGo_env.yml and the eDisGo_env_dev.yml.
• I have added new features to the corresponding whatsnew file