Fetch all commits and tags when building sdist

Otherwise the version comes up as "untagged" and the sdist can't be uploaded to PyPI.

Author: maresb

.github/workflows/pypi.yml

@@ -24,6 +24,7 @@ jobs:
     steps:
       - uses: actions/checkout@v3
         with:
+          fetch-depth: 0
           submodules: true
 
       - name: Build SDist