Replace setup.py with pyproject.toml

[moi15moi]

Fix https://github.com/enthought/comtypes/issues/480#issuecomment-1565784242 Note that when building the dist (with python -m build --sdist), it won't create a zip file anymore. It will be a tar.gz file. There is an issue about this, see https://github.com/pypa/setuptools/issues/3916, but honestly, I don't think it really matters.