Update JamesIves/github-pages-deploy-action action to v4.8.0

Author: renovate[bot]

.github/workflows/pkgdown.yaml

@@ -42,7 +42,7 @@ jobs:
 
       - name: Deploy to GitHub pages 🚀
         if: github.event_name != 'pull_request'
-        uses: JamesIves/github-pages-deploy-action@v4.5.0
+        uses: JamesIves/github-pages-deploy-action@v4.8.0
         with:
           clean: false
           branch: gh-pages