Feature: Add config file functionality

[Niccolum]

I can't find this in docs. Can we write config file (and add path to it, like in flake, pylint, gunicorn or other cli tools instead of flags?

[FredHappyface]

Currently no, but this is something I'd like to add

At the moment I'm thinking of adding a field into pyproject.toml perhaps with a fallback to a dot file

I shall also add this to my to-do

[Niccolum]

it would be awesome if there were both of these options!

[FredHappyface]

fixed in 2021.4