Integrate Black into CI

[bbugyi200]

While working on #1784, I spent too much time reformatting my code to make it look prettier (e.g. by wrapping long lines). Would there be any interest in integrating black into jedi's CI process? This is quickly becoming the standard (for good reason IMO). We would, ofcourse, have to blacken the codebase first.

[davidhalter]

No. I don't want to reformat everything for now. This does not mean this is a no forever, it's just for now I don't want it.

BTW: I also think that code styles is something devs obsess over and it shouldn't be that important.

[bbugyi200]

No. I don't want to reformat everything for now. This does not mean this is a no forever, it's just for now I don't want it.

@davidhalter I respect your decision. If this project does ever make this change, you should also consider integrating isort into CI. Adding / sorting imports manually is also something I don't like doing.

BTW: I also think that code styles is something devs obsess over and it shouldn't be that important.

I 1000% agree. That's why I use black, so I never have to think about code styling.