TOML set_env file support

[juditnovak]

This code change is addressing #3474, making sure that TOML config has the same support to apply set_env from file, as INI configuration does.

Resolves #3474

[gaborbernat]

You still plan to tackle this?

[juditnovak]

@gaborbernat Yes I do. Sorry for the silence, I was unavailable for a couple of days. Updated PR should be available early next week.

[gaborbernat]

@juditnovak tag me when ready 👍

[juditnovak]

@gaborbernat Sorry for the delay, the PR is ready. I keep thinking that I'm kind unhappy with the solution in terms of separation of concerns -- as part of the INI/TOML processing is happening on the level of each loader (__init__.py), while format-specific logic now is also hitting the shared (ideally generic) set_env module...
(Yet, otherwise set_env logic would need to "cascade up" to each loader's level :-/ )

In case I'm overlooking a different, more elegant solution, feel free to let me know, and I'm glad to adjust.

[juditnovak]

@gaborbernat The condition in question is removed (assuming that 'revert' meant removal of newly added code).

[gaborbernat]

Yeah, didn't forget about this, have the tab pinned. Just this week has been very busy at work and didn't get time to allocate to this, we should get this out by early next week though 👍

[juditnovak]

@gaborbernat Sure, thanks much for getting back.
No pressure, I just wanted to make sure to keep you in the loop :-)

[gaborbernat]

Fix released with https://github.com/tox-dev/tox/releases/tag/4.24.2