Fix test run

[levijackson]

When upgrading NextJS the babel config was removed and now the test run is failing.

    SyntaxError: /Users/levijackson/Sites/nextjs-blog/tests/unit/component/date.test.js: Support for the experimental syntax 'jsx' isn't currently enabled (25:16):

      23 | test('date renders', () => {
      24 |     act(() => {
    > 25 |         render(<Date dateString="2020-12-28" />, container);
         |                ^
      26 |     });
      27 |
      28 |     const testComponent = container.querySelector('time');

    Add @babel/preset-react (https://git.io/JfeDR) to the 'presets' section of your Babel config to enable transformation.
    If you want to leave it as-is, add @babel/plugin-syntax-jsx (https://git.io/vb4yA) to the 'plugins' section to enable parsing.