Update ws to the latest version 🚀 (#673)

* fix(package): update ws to version 6.1.0

* chore(package): update lockfile package-lock.json

Author: greenkeeper[bot]

package-lock.json

@@ -29,7 +29,7 @@
   },
   "dependencies": {
     "@babel/runtime": "^7.0.0",
-    "ws": "6.0.0",
+    "ws": "6.1.0",
     "xmlhttprequest": "1.8.0"
   },
   "devDependencies": {