upgrade the version of peaceiris/actions-gh-pages

Author: yosupo06

.github/workflows/document.yml

@@ -33,7 +33,7 @@ jobs:
           mv ../document_ja generated/ &&
           mv ../document_en generated/
       - name: Publish to github pages
-        uses: peaceiris/actions-gh-pages@v3.7.0-8
+        uses: peaceiris/actions-gh-pages@v3
         with:
           deploy_key: ${{ secrets.ACTIONS_DEPLOY_KEY }}
           publish_dir: ./tools/generated