refactor: Removed deprecation by switching to importlib.metadata

[tabedzki]

While the larger overhaul of the plugin architecture is being considered (#1251, this is a small fix to move away from pkg_resources and use importlib.metadata.

Nothing else has changed as this is solely to remove the deprecation warning when importing datajoint.

Edit: I tested it for Python 3.9 to 3.12 by doing

for version in 3.9 3.10 3.11 3.12; do
  uv run --python $version python -c 'import datajoint as dj; print(dj.__file__); print("Datajoint import successful")'; done

[dimitri-yatsenko]

Thank you, @tabedzki Please merge with the latest release.

Please also take a look at #1252 and #1253