Update dependency webpack-dev-server to v3.11.1

Author: renovate-bot

package.json

@@ -8,6 +8,6 @@
     "twilio-video": "^1.18.1"
   },
   "devDependencies": {
-    "webpack-dev-server": "3.7.1"
+    "webpack-dev-server": "3.11.1"
   }
 }