Remove with-cerebral example

[maxproske]

@cerebral/react is unable to build with next@latest, is no longer being maintained, was last updated 3 years ago, and requires a Babel plugin for TypeScript support. Therefore, I recommend removing this example.

Screenshot:

Documentation / Examples

• Make sure the linting passes by running pnpm build && pnpm lint
• The "examples guidelines" are followed from our contributing doc

[balazsorban44]

@maxproske if you have more of these, you can batch them into one PR, since there is nothing to review! 😄 🙏