readded the redirection rules to fix build warning

Author: halkazwini

.openpublishing.redirection.json

@@ -1,5 +1,15 @@
 {
     "redirections": [
+        {
+            "source_path": "articles/route-server/tutorial-protect-route-server.md",
+            "redirect_URL": "/azure/route-server/tutorial-protect-route-server-ddos",
+            "redirect_document_id": false
+        },
+        {
+            "source_path": "articles/route-server/routing-preference.md",
+            "redirect_url": "/azure/route-server/overview",
+            "redirect_document_id": false
+        },
         {
             "source_path": "articles/cloud-services-extended-support/deploy-visual-studio.md",
             "redirect_url": "/visualstudio/azure/cloud-services-extended-support?context=%2Fazure%2Fcloud-services-extended-support%2Fcontext%2Fcontext",