Lint won't pass - for now

[mpasternak]

In the old tox configuration I can find that there was lint running, which used black.

The current codebase is not very likely to be black-compatible, as you can see here: https://github.com/pytest-dev/pytest-splinter/runs/7750268300?check_suite_focus=true

I am against re-formatting the whole codebase. But I am totally for keeping up the code quality of changes introduced. On the other hand, isort or pyupgrade will mess the codebase a bit. As you can see in the lint run.

Is there any good solution? We can disable lint build target manually in GA, of course. This is one of the reasons I separated it from the "main" tests.

Ideas?