Support abi3 wheel tag for stable ABI

[rdb]

It appears that the only choices for building a wheel are to use the py3 tag for a pure Python package or the native platform tag (eg. cp312). Is there a way to use the abi3 tag, for projects using the limited API / stable ABI?

That would be greatly useful to avoid having to build separate wheels for each Python version.

[tttapa]

The latest development version has experimental support for the stable ABI: https://github.com/tttapa/py-build-cmake/blob/rework-0.2.0/docs/Config.md#wheel

I really need to find the time to actually release a new version, but unfortunately I've been pretty busy lately.