chore(package): update @babel/preset-env to version 7.3.4

Closes #6

Author: greenkeeper[bot]

package.json

@@ -30,7 +30,7 @@
     "@babel/plugin-syntax-dynamic-import": "7.2.0",
     "@babel/plugin-transform-runtime": "7.3.4",
     "@babel/polyfill": "7.2.5",
-    "@babel/preset-env": "7.1.5",
+    "@babel/preset-env": "7.3.4",
     "@babel/register": "7.0.0",
     "@babel/runtime": "7.1.5",
     "babel-core": "^7.0.0-bridge.0",