Update import in test

Update the import in __tests__\App.tsx to align with react-native

Author: Steven Cramer

__tests__/App.tsx

@@ -3,7 +3,7 @@ import React from 'react';
 import App from '../App';
 
 // Note: test renderer must be required after react-native.
-import * as renderer from 'react-test-renderer';
+import renderer from 'react-test-renderer';
 
 it('renders correctly', () => {
   const tree = renderer.create(