Build distribution and upload to PyPI

[NoraLoose]

This PR sets up a github workflow that builds C-Star locally, which creates distribution archives under the dist/ directory. These are the files that will be uploaded to PyPI when publishing a new release.

[dafyddstephenson]

Thanks Nora! Are we able to test this before merging? I think #147 might be potentially problematic here

[NoraLoose]

@dafyddstephenson definitely! The "Build distribution / test-built-dist" test that fails in the CI is that exact test. I think it fails for the same reason as #147.

[NoraLoose]

Obviously we won't merge before this issue is resolved. :)

[dafyddstephenson]

ah sorry, I'm debilitated by jetlag right now! I saw the workflow is only triggered on push to main and thought we'd have to merge to check it - didn't notice it was also on PR. I was hoping #168 might fix the static install issue as there's no longer a dynamically generated python file in the configuration, but no dice...