chore: add support for python 3.12

[irtazaakram]

Description:

This PR

• adds support for python 3.12
• drop support for python 3.8

Merge checklist:

• [ ] All reviewers approved
• [ ] CI build is green
• [ ] If adding new checks, followed how_tos/0001-adding-new-checks.rst
• [x] Changelog record added (if needed)
• [ ] Documentation updated (not only docstrings) (if needed)
• [ ] Commits are squashed

[feanil]

@irtazaakram can you also bump the version for this so we can do a release.