* 🎨 Make the GHA log is clean and colorized
This patch sets up root-level environment variables shared by all the
workflow jobs. They include:
* Disabling undesired `pip`'s warnings/suggestions
* Requesting the executed apps color their output unconditionally
* Letting `tox` pass those requests to underlying/wrapped programs
* Reformat without end of line comments. Group into sections.
* Avoid numerics for booleans where possible. Choose arbitrary numeric where any numeric is accepted.
Co-authored-by: Sviatoslav Sydorenko <wk@sydorenko.org.ua>