Python 3.12 docs failure

[jgallowa07]

When trying to build docs with python 3.12, The build and test workflow fails with

Run make -C docs clean
make: Entering directory '/home/runner/work/multidms/multidms/docs'
sphinx-apidoc -E -T -M -e -f -o . ../multidms
make: Leaving directory '/home/runner/work/multidms/multidms/docs'
make: Entering directory '/home/runner/work/multidms/multidms/docs'
sphinx-apidoc -E -T -M -e -f -o . ../multidms
Running Sphinx v7.2.6

Extension error:
Could not import extension sphinxcontrib.bibtex (exception: No module named 'pkg_resources')
make: *** [Makefile:23: html] Error 2
make: Leaving directory '/home/runner/work/multidms/multidms/docs'
Error: Process completed with exit code 2.