Migrate from pkg_resources to importlib_resources

[stevepiercy]

Python 3.12 removed the deprecated pkg_resources from being installed when creating a virtual environment. mxdev needs to migrate to importlib_resources.

See https://community.plone.org/t/error-while-running-make-install-command/19114

[jensens]

Got it, it is

• importlib.metadata to load entry_points (unstable API in standard library, how ugly, but well...)
• https://pypi.org/project/packaging/ for pkg_resources.Requirement.parse

[jensens]

Fixed, release next.