Modernise upload to PyPI

[fcooper8472]

Switch to modern build directive

i.e. use:

python -m build

rather than

python setup.py sdist bdist_wheel

Switch to trusted publishing

I have added this specific workflow as a trusted publisher on PyPI, which means we no longer require the token. Once this is tested we should delete that from the repo secrets.

Following best practice, I have split the workflow into two jobs, one for building the distribution files. This can be run on all pushes and PRs to check the wheel and sdist build. The other does the upload.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.54%. Comparing base (1c825f9) to head (cf4cb7a).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1734   +/-   ##
=======================================
  Coverage   99.54%   99.54%           
=======================================
  Files          97       97           
  Lines        9762     9762           
=======================================
  Hits         9718     9718           
  Misses         44       44           

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[MichaelClerx]

Looks good. Any idea if we can test it without doing a new release?

[fcooper8472]

I've tested everything except the actual upload step, but there's no way to test that without a release.

Could always do a subminor release to test, without any code changes?

[MichaelClerx]

Yeah probably best to do an 0.6.1 immediately then, so we can delete the token etc before we forget about it