fix deploy job action version

Author: houqp

.github/workflows/deploy.yml

@@ -23,7 +23,7 @@ jobs:
           mdbook build
 
       - name: Deploy 🚀
-        uses: JamesIves/github-pages-deploy-action@4
+        uses: JamesIves/github-pages-deploy-action@v4
         with:
           branch: gh-pages
           folder: book