chore(package): update webpack-manifest-plugin to version 2.0.2

Closes #766

package.json

@@ -75,7 +75,7 @@
     "uglify-js": "^3.1.10",
     "unfetch": "^3.0.0",
     "webpack": "^3.4.1",
-    "webpack-manifest-plugin": "^1.3.2"
+    "webpack-manifest-plugin": "^2.0.2"
   },
   "engines": {
     "node": ">= 8"