Updated merge2, as used by our Gulp build process

This is an internal development dependency and will have no impact on downstream consumers.

Author: JeremyCaney

OnTopic.Editor.AspNetCore/package-lock.json

@@ -24,7 +24,7 @@
     "jquery-validation": "^1.19.2",
     "jquery.are-you-sure": "^1.9.0",
     "jshint": "^2.11.1",
-    "merge2": "^1.3.0",
+    "merge2": "^1.4.1",
     "popper.js": "^1.16.1"
   }
 }