update dependencies

Author: hauner

package-lock.json

@@ -30,7 +30,7 @@
     "eslint-plugin-standard": "~4.0",
     "fancy-log": "~1.3",
     "fs-extra": "~8.1",
-    "gulp": "~4.0",
+    "gulp": "~4.0.2",
     "gulp-concat": "~2.6",
     "gulp-connect": "~5.7",
     "gulp-eslint": "~6.0",