importlib_resource new API

[HelgeKrueger]

When running tests with python 3.11, I get the following warning:

../../../root/.cache/pypoetry/virtualenvs/bovine-herd-jY87IYlK-py3.11/lib/python3.11/site-packages/multiformats_config/multicodec.py:80
  /root/.cache/pypoetry/virtualenvs/bovine-herd-jY87IYlK-py3.11/lib/python3.11/site-packages/multiformats_config/multicodec.py:80: 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 importlib_resources.open_text("multiformats_config", "multicodec-table.json", encoding="utf8") as _table_f:

My reading of https://importlib-resources.readthedocs.io/en/latest/using.html#migrating-from-legacy says that fixing this would mean going Python 3.9 only. Is there any objection to doing this?

If not, I can prepare a pull request.