chore(deps): update dependency webpack to v4.28.4

Author: renovate-bot

package.json

@@ -53,7 +53,7 @@
     "typedoc": "0.14.0",
     "typescript": "3.2.2",
     "uuid": "3.3.2",
-    "webpack": "4.28.3",
+    "webpack": "4.28.4",
     "webpack-cli": "3.2.1"
   },
   "scripts": {