CI: move test to pythons 3.8, 3.10 and 3.11

TODO

• update CI
• check logs for any deprecation warning

warnings

load_module

nxtomomill/test/test_plugins.py::test_get_plugins_instances
  <frozen importlib._bootstrap>:283: DeprecationWarning: the load_module() method is deprecated and slated for removal in Python 3.12; use exec_module() instead