CI: set concurrency

[Borda]

Found this use-case for GH action and Tox - https://github.com/tox-dev/tox-gh; what do you think?

[hugovk]

I don't really understand what tox-gh brings, beyond duplicating the Python version numbers in test.yml and in tox.ini

Please could you elaborate on the benefits?

[Borda]

Please could you elaborate on the benefits?

You are probably right, just found it easier to read/follow...

[JulienPalard]

I'm not a fan of bringing yet another dependency here. If it was me alone I would just have a single github build (with multiple actions/setup-python in it, yes it works) running a single tox instance: trying to keep it simple, a bit like in 45af71c.

[Borda]

it was me alone I would just have a single github build (with multiple actions/setup-python in it, yes it works) running a single tox instance: trying to keep it simple

Yes, agree but since the Tox is here, it is better to check it and the simplest was to do so is use it... So to say reduce dead code =)

a bit like in 45af71c.

Well, this one is also strange with redundant python setups...

[hugovk]

Anyway, back to this PR.

I think the concurrency: changes are useful, and let's revert the others.

[Borda]

Anyway, back to this PR.

OK will update PR and it's name accordingly

[hugovk]

Thanks!

[Borda]

@hugovk so fine to land? 🐿️

[Borda]

@hugovk is it fine now, or shall I update something else? 🦩