update babel core

Author: koddsson

package-lock.json

@@ -21,7 +21,7 @@
   },
   "devDependencies": {
     "@babel/cli": "^7.2.3",
-    "@babel/core": "^7.2.2",
+    "@babel/core": "^7.3.3",
     "@babel/plugin-transform-modules-umd": "^7.2.0",
     "babel-preset-github": "^3.0.0",
     "chai": "^4.2.0",