Merge pull request #23 from matplotlib/dependabot/github_actions/peaceiris/actions-gh-pages-4.0.0

Bump peaceiris/actions-gh-pages from 3.9.3 to 4.0.0

Author: tacaswell

.github/workflows/docs.yml

@@ -29,7 +29,7 @@ jobs:
 
       - name: Publish
         if: ${{ env.IS_RELEASE == 'true' }}
-        uses: peaceiris/actions-gh-pages@373f7f263a76c20808c831209c920827a82a2847 # v3
+        uses: peaceiris/actions-gh-pages@4f9cc6602d3f66b9c108549d475ec49e8ef4d45e # v4.0.0
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
           publish_dir: ./docs/build/html