incoming pkg_resources deprecation from setuptools

  /builds/fastspm/pyfastspm/pyfastspm/tools/frame_artists.py:12: UserWarning: pkg_resources is deprecated as an API. See https://setuptools.pypa.io/en/latest/pkg_resources.html. The pkg_resources package is slated for removal as early as 2025-11-30. Refrain from using this package or pin to Setuptools<81.
    from pkg_resources import resource_filename

xref: https://gitlab.com/fastspm/pyfastspm/-/jobs/10883045962#L65