fix: skip-existing on TestPyPI to avoid 400 on re-upload

Author: LGDiMaggio

.github/workflows/publish.yml

@@ -49,6 +49,7 @@ jobs:
         uses: pypa/gh-action-pypi-publish@release/v1
         with:
           repository-url: https://test.pypi.org/legacy/
+          skip-existing: true
 
   publish-pypi:
     name: Publish to PyPI