test(GithubCard): add snapshot testing

src/components/GithubCard/GithubCard.test.tsx

@@ -0,0 +1,46 @@
+import React from 'react';
+import renderer from 'react-test-renderer';
+import { render } from '@testing-library/react';
+import GithubCard from './GithubCard';
+
+describe('GithubCard', () => {
+  const github = {
+    profile: {
+      username: 'sabertazimi',
+      avatar: 'https://avatars.githubusercontent.com/u/12670482?v=4',
+      bio: 'CS',
+      location: 'Wuhan',
+      url: 'https://github.com/sabertazimi',
+      followers: 42,
+      followersUrl: 'https://github.com/sabertazimi/followers',
+      following: 185,
+      followingUrl: 'https://github.com/sabertazimi/following',
+      createDate: 'Sat May 30 2015',
+    },
+    repos: [
+      {
+        name: 'hust-lab',
+        stars: 22,
+        language: 'C',
+        repoUrl: 'https://github.com/sabertazimi/hust-lab',
+      },
+      {
+        name: 'awesome-notes',
+        stars: 22,
+        language: 'JavaScript',
+        repoUrl: 'https://github.com/sabertazimi/awesome-notes',
+      },
+      {
+        name: 'dragon-zsh-theme',
+        stars: 11,
+        language: 'Zsh',
+        repoUrl: 'https://github.com/sabertazimi/dragon-zsh-theme',
+      },
+    ],
+  };
+
+  test('should render correctly (snapshot)', () => {
+    const tree = renderer.create(<GithubCard github={github} />).toJSON();
+    expect(tree).toMatchSnapshot();
+  });
+});