Adopt native TOML `tox` support

[paddyroddy]

Is Your Feature Request Related to a Problem? Please Describe

Following tox-dev/tox#3353 ymyzk/tox-gh-actions#197, it will at some be possible to have full native TOML support. I tried this for now and couldn't get it to work, so we might need to wait a bit. This would involve removing the lecacy INI format.

Describe the Solution You'd Like

No response

Describe Alternatives You've Considered

No response

Additional Context

No response

[gaborbernat]

https://tox.wiki/en/4.21.0/config.html#pyproject-toml-native You should be able to do it all, in case you're running into problems, please feel free to tag me.

[gaborbernat]

Following tox-dev/tox#3353 ymyzk/tox-gh-actions#197,

Any reason why not use https://github.com/tox-dev/tox-gh instead? 😆

[paddyroddy]

@gaborbernat I have made a start on this and using tox-gh. I'm unsure of how to port the [gh] in the legacy_tox_ini section to TOML, astro-informatics/sleplet#421

[gaborbernat]

https://github.com/tox-dev/tox-gh?tab=readme-ov-file#examples

[paddyroddy]

@gaborbernat got this working in #460 😄