ci: Add workflow to deploy to distributions to TestPyPI and PyPI

[matthewfeickert]

Add GHA based workflow to release a sdist and wheel to:

• TestPyPI on tags
• PyPI on GitHub releases

Locally on master run:

$ git checkout master && git pull # verify that you're on master and synced with GitHub
$ bump2version <part> # bump the version and create a commit and tag
$ git push origin master --tags # push the commit and the tag to GitHub, causing TestPyPI to publish

• Got to TestPyPI (https://test.pypi.org/project/recast-atlas/) to look if the release looks okay
• Then on GitHub:
  1. Go to releases: https://github.com/recast-hep/recast-atlas/releases
  2. Click "Draft a new release"
  3. On the new page enter the tag you just pushed (e.g. v0.1.0) in the "Tag version" box and the "Release title" box (to make it easy unless you really want to get descriptive)
  4. Enter any release notes and click "Publish release"
• This then kicks of the publication CD workflow that will use the PyPI API key to publish.

* Publish sdists and wheels to TestPyPI through pushed tags triggered through push events
* Publish sdists and wheels to PyPI through published release events triggered through GitHub releases
   - c.f. https://docs.github.com/en/free-pro-team@latest/actions/reference/events-that-trigger-workflows#release
* Remove publishing setup on deploy.yml workflow

[matthewfeickert]

@lukasheinrich I need you to either give me permissions on TestPyPI and PyPI to the package or I need you to add API tokens for PyPI and TestPyPI.

[matthewfeickert]

Thanks for the merge @lukasheinrich. Can you either give me permissions on TestPyPI and PyPI to the package or can you add API tokens for PyPI and TestPyPI?

[matthewfeickert]

Can you either give me permissions on TestPyPI and PyPI to the package or can you add API tokens for PyPI and TestPyPI?

Thanks for doing this @lukasheinrich! This workflow is ready to go now. 👍

As soon as we fixup the Docker deploy workflow then I think things are ready to bump a new release using the workflow described above. Actually, I should a developer.md or something that describes how to do a release.