Add support for Cypress 7 Component Testing

[Vadorequest]

Why: https://www.cypress.io/blog/2021/04/06/introducing-the-cypress-component-test-runner/

Might not be necessary for the demo itself, but supporting Component testing would probably be a good thing. On the other hand, it creates another way to do it (compared to what's already available) and might confuse devs about what tool to use.

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Next.js config:
https://docs.cypress.io/guides/component-testing/framework-configuration#Next-js-Webpack-4

Next.js example:
https://github.com/cypress-io/cypress-component-examples