Lint Python scripts and add GitHub Action

[PabloAlexis611]

This PR has aesthetic-only code changes performed automatically by the linting tools:

• isort: https://pypi.org/project/isort/
• black: https://pypi.org/project/black/

It also adds a new GitHub Action to lint the Python code using these same tools. This is a sample run in my forked repo of this new action:

[SIsilicon]

Oops! It's not building OK.

[SIsilicon]

Ah, it's a problem in the master branch. I'll pull this in anyway then. Thanks!