Consider using parallel pylint

[dabacon]

Pylint is by far one of the slowest parts of the CI suite. It has a parallel flag, -j . On my local box, doing j=4 sped up pylint from 2.5 minutes to 1 minute.

[balopat]

We can try - I have had moderate success on the Github Actions machines with parallelization - namely the sphinx build actually just hung when I set -j auto, but also -j 2 didn't help either. Not sure why. Maybe there is some kind of cpu throttling / oversubscription / virtualization / containerization overhead :) or maybe it's just specific to sphinx and not pylint. Worth a try!