chore(package): update webpack to version 4.12.0

Author: greenkeeper[bot]

package.json

@@ -29,7 +29,7 @@
     "stylelint-order": "0.8.1",
     "stylelint-scss": "3.1.0",
     "stylelint-webpack-plugin": "0.10.5",
-    "webpack": "4.11.1",
+    "webpack": "4.12.0",
     "webpack-cli": "3.0.3"
   },
   "browserslist": [