Revisit test and publish workflows

[mphoward]

Currently, the publish workflow is independent of the test workflow and triggered by publishing of a release. It may be desirable to:

• Make sure tests run on tag that becomes a release. This probably means making sure tags trigger the test.
• Check package uploads to TestPyPI before going to PyPI.

One possible solution is to build the package for distribution at the end of the test run (on every commit) and save it as an artifact. If the commit being tested is a version tag, it should then also go to TestPyPI.

If possible, the publish script should then just grab the artifact from the test, rather than build it again.

[clpetix]

@mphoward, we should edit our test workflow to compile and run MPI tests on HOOMD-blue before tagged releases.

[mphoward]

Agreed! Feel free to make a PR doing so. You may be able to adapt from the azplugins unit tests, since those build HOOMD.