Publish to PYPI from github release workflow

[icarito]

Lets go full automation!
🤖

[icarito]

Okay this worked but let's tweak it.

• Pypi should publish as "prerelease" versions tagged as v#.#.#{dev|alpha|beta}
• Pypi should publish as a full release versions tagged as v#.#.# (without any textual suffix)
• Pypi workflow should ignore all tagged with suffix different to dev, alpha, beta (e.g. test)

[icarito]

This is still messy - seems like there's some inconsistencies in handling setuptools-scm's version numbers and I'm publishing prereleases as releases in pypi (oops).