chore(package): update yargs to version 14.2.0

Closes #30

Author: greenkeeper[bot]

package.json

@@ -113,7 +113,7 @@
     "webpack": "^4.33.0",
     "webpack-cli": "^3.3.3",
     "webpack-node-externals": "^1.7.2",
-    "yargs": "^13.2.4",
+    "yargs": "^14.2.0",
     "zone.js": "^0.9.1"
   },
   "engines": {