Add automatic style formatting

[russelldj]

It would be useful to choose a style format and then automatically enforce this. In geograypher we use isort for import ordering and black for code formatting. These are managed by github action so it runs automatically on pushes to main and PRs. I think this has worked well and I'd recommend doing the same.

[youngdjn]

This would be great! @asidhu0, would you be willing to take this on, given your experience setting this up for Geograypher?