Test openedx-events on Python 3.11

This repository is a depedency of edx-platform and needs to be upgraded to Python 3.11 before the Readwood release is cut (mid-April).

[x] Requirements are compiled with Python 3.8
[x] Tests are run on Python 3.8 and 3.11
[ ] (Optional) Tests are also run with 3.12 and passing or 3.12 issues are ticketed.
[ ] Classifiers in setup.py setup.cfg or pyproject.toml indicate Python 3.11 support
[x] A new version is release to PyPI
[ ] A PR is merged to edx-platform to use the new version

openedx / openedx-events