Reconfiguring `black` workflow

[laserkelvin]

This PR reconfigures the black formatter part of the lint-format workflow by removing the autocommit action, and relying on the official psf version of the Github action.

The intention now is that the black workflow will simply check files within the p3 source for modifications that black would perform, as opposed to making and committing the changes.

Related issues

Fixes #19

Proposed changes

List out—with high level descriptions—what the commits within this PR do:

• Remove auto-commit action which wasn't working as intended, per #19
• Remove Python setup within black workflow
• Remove black installation within workflow
• Change to using psf/black@stable for configuring and running black on the code
• Added black options per #19; --check --verbose --diff

[laserkelvin]

I could test the workflow, too, by pushing some poorly formatted code to see if it triggers the action?

[Pennycook]

I could test the workflow, too, by pushing some poorly formatted code to see if it triggers the action?

Good idea. Let's do that.

[laserkelvin]

@Pennycook please take a look at the logs, but it seems to work - I'll revert and we can merge after that

[Pennycook]

@Pennycook please take a look at the logs, but it seems to work - I'll revert and we can merge after that

Looks perfect!

[laserkelvin]

I've reverted the fudge on _utils.py and the test passed. Merging!