Python: use of deprecated importlib API

Running the tests gives:

python/constellation/core/__init__.py:19
  /home/stephan/Projects/constellation/python/constellation/core/__init__.py:19: DeprecationWarning: read_text is deprecated. Use files() instead. Refer to https://importlib-resources.readthedocs.io/en/latest/using.html#migrating-from-legacy for migration advice.
    __version_code_name__ = importlib.resources.read_text("constellation.core", "version_code_name").strip("\n")

../../../../usr/lib/python3.12/importlib/resources/_legacy.py:79
  /usr/lib/python3.12/importlib/resources/_legacy.py:79: DeprecationWarning: open_text is deprecated. Use files() instead. Refer to https://importlib-resources.readthedocs.io/en/latest/using.html#migrating-from-legacy for migration advice.
    with open_text(package, resource, encoding, errors) as fp:

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html

Should be easy enough to fix, will do