Add tests for examples

[sagikazarmark]

It would be nice to add tests for examples to verify they work as they are supposed to.

I propose we create a GitHub Actions workflow that:

• runs daily to make sure examples work
• is a matrix workflow for each example
• runs kubectl apply (optionally starting with running setup) and runs check to make sure it works as expected

We could potentially also code them as e2e tests using the kube e2e framework.