feat: remove unused React imports (facebook#9853)

Author: mrmckeb

packages/cra-template/template/src/App.js

@@ -1,4 +1,3 @@
-import React from 'react';
 import logo from './logo.svg';
 import './App.css';
 

packages/cra-template/template/src/App.test.js

@@ -1,4 +1,3 @@
-import React from 'react';
 import { render, screen } from '@testing-library/react';
 import App from './App';