Update GitHub Pages deploy action version

Author: VisruthSK

.github/workflows/pkgdown.yaml

@@ -66,7 +66,7 @@ jobs:
         shell: Rscript {0}
 
       - name: Deploy to GitHub pages 🚀
-        uses: JamesIves/github-pages-deploy-action@v4.5.0
+        uses: JamesIves/github-pages-deploy-action@v4
         with:
           clean: false
           branch: gh-pages