CAPI: add CAPI e2e jobs to provider repos

In the cluster-capi-operator repository are present several CAPI E2E tests for specific providers.

We run these tests on every PR that lands on that repository.

In order to test rebases for the cluster-api providers we want to run these tests also there to prove rebase PRs are not breaking CAPI functionality.

DoD:

• Set techpreview openshift E2E jobs for the cluster-api providers to make sure the build doesn't break the TP payload
• Set techpreview CAPI E2E jobs for cluster-api providers repositories for providers where an corresponding e2e test is present in the cluster-capi-operator
  • for now only AWS, GCP and IMBCloud have E2Es
• Add a target/script in the cluster-api providers repositories for running the E2E CAPI tests, where it applies.