Upload attestations to PyPI

They'll be cool to look at or something

Author: alex

.github/workflows/release.yml

@@ -54,3 +54,5 @@ jobs:
       - name: publish
         if: github.event_name == 'push'
         uses: pypa/gh-action-pypi-publish@8a08d616893759ef8e1aa1f2785787c0b97e20d6 # v1.10.0
+        with:
+          attestations: true