Log Message:
py-cffi: updated to 1.15.0

v1.15.0
=======
* Fixed MANIFEST.in to include missing file for Windows arm64 support
* Fixed Linux wheel build to use gcc default ISA for libffi
* Updated setup.py Python trove specifiers to currently-tested Python versions
* CPython 3.10 support (including wheels)
* MacOS arm64 support (including wheels)
* Initial Windows arm64 support
* Misc. doc and test updates