fix tests

package.json

       ]
     }
   }
-}
+}

playground/src/screens/LifecycleScreen.js

 const React = require('react');
 const { Component } = require('react');
 
-const { View, Text, Button, Platform } = require('react-native');
+const { View, Text, Button } = require('react-native');
 
 const Navigation = require('react-native-navigation');
 const testIDs = require('../testIDs');