Python wheel's macOS deployment target is incorrect

[bwoodsend]

What version of protobuf and what language are you using?
Version: 4.21.8
Language: Python

What operating system (Linux, Windows, ...) and version?
macOS 12.6 with M1 chip

What runtime / compiler are you using (e.g., python version or gcc version)
Python 3.9.9

What did you do?
Steps to reproduce the behavior:

# Download the latest protobuf wheel and unpack it 
$ pip download --no-deps protobuf
$ unzip protobuf-4.21.8-cp37-abi3-macosx_10_9_universal2.whl
# Check the deployment target of the x86_64 slice of the one compiled file it contains
$ otool -mcpu=x86_64 -l google/_upb/_message.abi3.so | grep minos 
    minos 11.3
    minos 11.3

What did you expect to see

The macOS deployment target (a.k.a. the minimum supported version of macOS that this library supports - -mmacosx-version-min parameter to clang) of the compiled extension module should match that which the .whl file's filename declares.

What did you see instead?

The wheel declares support for macOS >= 10.9 but google/_upb/_message.abi3.so is compiled only for macOS >= 11.3. This means that for any macOS user with macOS version >=10.9 and <11.3 who runs pip install protobuf, pip will happily install this wheel thinking that it's compatible when it might not be, potentially leading to messy symbol load errors or crashes at runtime.

Anything else we should know about your project / environment

Nope.