Migrate the setup.py packaging file to a PEP517 compliant pyproject.toml file

[rndubs]

Installing unification from PyPI must first build a wheel from the sdist since a wheel isn't deployed to PyPI. The unification packaging (setup.py, setup.cfg) is not PEP517 compliant, which forces pip to go through the legacy build entry points during installation. Pip has deprecated the legacy setup.py bdist_wheel entry point. To resolve this issue, migrate the unification packaging to a pyproject.toml file as outlined in PEP517.

Related links:

• https://peps.python.org/pep-0517/
• https://pip.pypa.io/en/stable/news/#v25-1
• Deprecate legacy setup.py bdist_wheel mechanism for building projects pypa/pip#6334
• Deprecate the setup.py bdist_wheel code path pypa/pip#13319