chore: update example.

Author: jaywcjlove

package.json

@@ -6,6 +6,7 @@
     "@testing-library/jest-dom": "^5.16.2",
     "@testing-library/react": "^12.1.3",
     "@testing-library/user-event": "^13.5.0",
+    "@uiw/react-github-corners": "~1.5.3",
     "react": "^17.0.2",
     "react-dom": "^17.0.2",
     "react-scripts": "5.0.0",

src/App.js

@@ -1,10 +1,15 @@
 import { Button } from 'uiw';
+import GitHubCorners from '@uiw/react-github-corners';
 import logo from './logo.svg';
 import './App.css';
 
 function App() {
   return (
     <div className="App">
+      <GitHubCorners
+        target="__blank"
+        href="https://github.com/uiwjs/uiw-example-create-react-app"
+      />
       <header className="App-header">
         <img src={logo} className="App-logo" alt="logo" />
         <p>