Update webpack to the latest version 🚀 (#1220)

* chore(package): update webpack to version 4.39.2

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

Author: greenkeeper[bot]

package-lock.json

@@ -99,7 +99,7 @@
     "sass-loader": "7.2.0",
     "style-loader": "1.0.0",
     "svg-prep": "1.0.4",
-    "webpack": "4.39.1",
+    "webpack": "4.39.2",
     "webpack-cli": "3.3.6"
   },
   "scripts": {