chore: add support for python 3.12

[rgimen3z]

• Remove all mentions of python 3.7, since it isn't supported according to the pyproject.toml

• Add python 3.12 as a supported version and update documentation accordingly

• Upgrade dependencies and unpin the ones that seemed to be blocking the support for python 3.12

• A few tweaks to appease the updated versions of mypy and pylint

• I have read the contributing guidelines

[rgimen3z]

didn't know who to tag, so adding some of the most recent contributors/reviewers: @newhouse, @danielhusar, @fostimus

[benogle]

Hey @rgimen3z thanks for this. We're working through a couple other related upgrades in #58 and #64. #58 has a pydantic blocker and #64 should solve it. Once we have #64 worked out, we'll incorporate your changes into the upgrades of all dependencies. We should be able to get to all that in the next week or so