Update babel7 to the latest version 🚀 (#707)

* chore(package): update @babel/plugin-proposal-class-properties to version 7.2.3

* chore(package): update @babel/plugin-transform-flow-strip-types to version 7.2.3

* chore(package): update @babel/polyfill to version 7.2.3

* chore(package): update @babel/preset-env to version 7.2.3

* chore(package): update lockfile package-lock.json

Author: greenkeeper[bot]

package-lock.json

@@ -34,12 +34,12 @@
   },
   "devDependencies": {
     "@babel/core": "^7.2.2",
-    "@babel/plugin-proposal-class-properties": "^7.2.1",
+    "@babel/plugin-proposal-class-properties": "^7.2.3",
     "@babel/plugin-transform-flow-comments": "^7.2.0",
-    "@babel/plugin-transform-flow-strip-types": "7.2.0",
+    "@babel/plugin-transform-flow-strip-types": "7.2.3",
     "@babel/plugin-transform-runtime": "7.2.0",
-    "@babel/polyfill": "7.0.0",
-    "@babel/preset-env": "7.2.0",
+    "@babel/polyfill": "7.2.3",
+    "@babel/preset-env": "7.2.3",
     "@babel/preset-react": "7.0.0",
     "@parse/minami": "^1.0.0",
     "babel-core": "^7.0.0-bridge.0",