Migrate to flit, pdm, or hatch

[patrick91]

Currently, our build step look like this:

python -m pip install build twine
python -m build
python -m twine check dist/*
python -m twine upload dist/*

I think we can migrate to a tool like flit, pdm or hatch, which won't require us to have a setup.py file (and we can migrate to pyproject.toml)