chore(package): update babel-plugin-transform-class-properties to version 6.22.0 (#835)

package.json

@@ -49,7 +49,7 @@
     "babel-plugin-module-resolver": "2.4.0",
     "babel-plugin-react-require": "^3.0.0",
     "babel-plugin-transform-async-to-generator": "6.16.0",
-    "babel-plugin-transform-class-properties": "6.19.0",
+    "babel-plugin-transform-class-properties": "6.22.0",
     "babel-plugin-transform-object-rest-spread": "6.22.0",
     "babel-plugin-transform-runtime": "6.22.0",
     "babel-preset-es2015": "6.22.0",