Use Black from Poetry
There is a difference between Black version 18.9b0 emended into the docker container Debian Buster from the Debian package. Using black from PyPi within Poetry environment shouldn’t rise such issues. In this case we would get 19.3b0 version. This shortcut was set-up to speed-up the format job from 1min30 to 45s, to avoid installing runtime and dev dependencies.
- CI: Install dependencies, use black from Poetry environment