Using black formatting

[SVilgelm]

Fix #55

[ziirish]

I think it would make sense to replace the current lint step with black --check as another commit in this PR.

[ziirish]

Could you please rebase?
I think we'd also need to update the CONTRIBUTING guidelines stating that we are using black for the code formatting.

Thanks

[j5awry]

I reviewed based on the following:

1. the github action
2. making sure black was added to a requirements file

I didn't go through each format change, as I trust black (since i use it personally)

[ziirish]

Like @j5awry, I didn't review all the changes per say, just the interesting bits (CONTRIBUTING guidelines, workflows, etc.)