bump gh-action-pypi-publish version

Author: slayoo

.github/workflows/tests+pypi.yml

@@ -146,8 +146,8 @@ jobs:
         name: dist
         path: dist
     - if: github.event_name == 'push' && github.ref == 'refs/heads/main'
-      uses: pypa/gh-action-pypi-publish@master
+      uses: pypa/gh-action-pypi-publish@unstable/v1
       with:
         repository_url: https://test.pypi.org/legacy/
     - if: startsWith(github.ref, 'refs/tags')
-      uses: pypa/gh-action-pypi-publish@master
+      uses: pypa/gh-action-pypi-publish@unstable/v1