Investigate unit test failures with python 3.6, 3.7, 3.12

[smjoshiatglobus]

• 3.6: Not available on ubuntu-22.04
• 3.7: Results in failures in test_cli.py
• 3.12: pkg_resources not supported

  • pydicom/data/data_manager.py:112: in get_external_sources
    from pkg_resources import iter_entry_points
    E   ModuleNotFoundError: No module named 'pkg_resources'
    

  • Probably due to loading incorrect version of pydicom. The latest version does not use pkg_resources, changed in Commit f5eeee