remove pre-commit

[dylanmcreynolds]

Pre-commit is great in theory and it's fantastic to be able to enforce the use of black to proivde consistent formatting.

But it's buggy and hard to use.

I'm ripping it out. We still call flake8 in the github action, but no longer use pre-commit.

[jl-wynen]

If you still want to enforce formatting, you can set up an action to format the code and auto commit the result. I can point you to our setup if you're interested.