Update GitHub Pages Publish action

Author: tpeczek

.github/workflows/gh-pages.yml

@@ -40,7 +40,7 @@ jobs:
         name: docfx
         path: DocFx.AspNetCore.ServerSentEvents/wwwroot
     - name: Publish
-      uses: JamesIves/github-pages-deploy-action@4.4.1
+      uses: JamesIves/github-pages-deploy-action@v4.4.1
       with:
         branch: gh-pages
         folder: DocFx.AspNetCore.ServerSentEvents/wwwroot