fix github alert

Author: helight

web2/package.json

@@ -51,7 +51,7 @@
     "vue-template-compiler": "^2.5.2",
     "webpack": "^3.6.0",
     "webpack-bundle-analyzer": "^2.9.0",
-    "webpack-dev-server": "^2.9.1",
+    "webpack-dev-server": ">=3.1.11",
     "webpack-merge": "^4.1.0"
   },
   "engines": {