Add test for Emoji

app/soapbox/components/ui/emoji/__tests__/emoji.test.tsx

@@ -0,0 +1,12 @@
+import React from 'react';
+
+import { render, screen } from '../../../../jest/test-helpers';
+import Emoji from '../emoji';
+
+describe('<Emoji />', () => {
+  it('renders the given text', () => {
+    render(<Emoji emoji='smile' />);
+
+    expect(screen.getByRole('img').getAttribute('alt')).toBe('smile');
+  });
+});