CI: add linux x86 32bit wheels

[patacca]

Add the wheels for linux i686 (x86 32 bit) both for gnu libc and musl.

[mattip]

Please justify adding to the project's maintenance burden. This reverts the decision made in the 1.22 release to drop 32 bit linux wheels

Also note that 32 bit wheels are only provided for Python 3.8 and 3.9 on Windows, all other wheels are 64 bits on account of Ubuntu, Fedora, and other Linux distributions dropping 32 bit support.

[mattip]

The original contributor did not respond. Closing.

[patacca]

Sorry, I mentally closed the issue and forgot about it 🤦
I didn't notice that 32bit wheels have been intentionally discontinued. The rationale makes perfect sense.