Use v1 of GitHub action pypa/gh-action-pypi-publish (#1744)

The `master` branch version has been sunset, see
https://github.com/pypa/gh-action-pypi-publish#-master-branch-sunset-

At the moment there's no diff between `master` and `release/v1`, see
pypa/gh-action-pypi-publish@master...release/v1

Author: michael-k

.github/workflows/release.yml

@@ -36,7 +36,7 @@ jobs:
 
       - name: Upload packages to Jazzband
         if: github.event.action == 'published'
-        uses: pypa/gh-action-pypi-publish@master
+        uses: pypa/gh-action-pypi-publish@release/v1
         with:
           user: jazzband
           password: ${{ secrets.JAZZBAND_RELEASE_KEY }}