Fix load_module deprecation warnings for Python >= 3.10.

[fschulze]

The lint and mypy errors are also on master. I guess newer mypy added some errors and the Python versions changed because of latest Python release since last run 6 months ago.

[malthe]

I don't understand why linting errors mean we have to change this code? Did something not work before?

[fschulze]

This change is only about the deprecation warning. I only meant that current tox run isn't passing, because of unrelated changes outside of Chameleon and this PR.

[malthe]

OK, I somehow thought all of this had been revamped in #396.

[fschulze]

That was how to determine the module name etc. This is about changes in the importlib and zipimport modules in Python 3.10. It looks like the removal of those methods was planned for 3.12 but postponed.

[malthe]

Not sure why the testing workflow was disabled. Yes, the repository has had no activity for 60 days, but now it has thanks to your pull request.

There seems to be some minor problems: https://github.com/malthe/chameleon/actions/runs/12280815714/job/34268167089.