chore(package): update webpack-cli to version 3.3.9

Closes #159

Author: greenkeeper[bot]

package.json

@@ -22,7 +22,7 @@
     "devDependencies": {
         "copy-webpack-plugin": "4.5.3",
         "webpack": "4.29.6",
-        "webpack-cli": "3.1.2",
+        "webpack-cli": "3.3.9",
         "webpack-dev-server": "3.2.1"
     }
 }