chore(deps): update peaceiris/actions-gh-pages action to v4

Author: renovate[bot]

.github/workflows/push.yaml

@@ -59,7 +59,7 @@ jobs:
           directory: gh-pages
 
       - name: Deploy
-        uses: peaceiris/actions-gh-pages@v2
+        uses: peaceiris/actions-gh-pages@v4
         env:
           PERSONAL_TOKEN: ${{ secrets.PERSONAL_TOKEN }}
           PUBLISH_BRANCH: gh-pages