Github Actions: Linux runners seem to be missing python 3.8

[EmilDohne]

It appears something changed on the runner config making these no longer run 3.8

https://github.com/EmilDohne/PhotoshopAPI/actions/runs/25644703834

[EmilDohne]

Looks like it is just gone so we'll have to drop build support for it like we did with windows and macos

[EmilDohne]

pypa/manylinux#1882