Improving dependency management as per ADR 0001

[jaredsnyder]

This is a PR to improve the dependency management by adding a requirements.txt file autogenerated by a script via pip-tools. More details in the ADR 0001 doc in docs/adrs. Added a pyproject.toml to consolidate a lot of the config too.

Non-exhaustive list of things I need reviewers to double-check:

• Make sure nothing from the setup.cfg and setup.py that we need got left out of the pyproject.toml. There was some stuff that seemed irrelevant (IE all the isort config from the setup.cfg which we don't seem to be using) so make sure that is actually irrelevant.
• that tox works locally for you
• that the auto-generated version is working as expected
• using the requirements.txt works as expected
• check to make sure I set up dependabot correctly

Also questions:

• Do we want to use this PR to clean up the tox.ini? It looks significantly different than jetstreams. If so I'll need some help understanding the difference probably.
• Do we need to build a universal wheel given we don't support python2?

Fixes #202

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 84.45%. Comparing base (adeb867) to head (58e3927). Report is 9 commits behind head on main.

Additional details and impacted files

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[mikewilli]

Do we want to use this PR to clean up the tox.ini? It looks significantly different than jetstreams. If so I'll need some help understanding the difference probably.

I don't think the differences are a concern. I don't see any differences that are important to change, and changes would probably be made to the jetstream side if anything (e.g., incorporate rust).

Do we need to build a universal wheel given we don't support python2?

No, not as far as I understand at least.