OpenShiftClientProducer tests

[manusa]

Description

Closes #35525

As discussed, #35525 can't be merged since there is no support for the @Specializes annotation.

This PR contains the tests that were introduced in #35525 to ensure the behavior of the beans provided by OpenShiftClientProducer.

From #35525 (comment):

• BeanDefaultsTest: A user is able to inject KubernetesClient and OpenShiftClient fields.
  The injected KubernetesClient instance should be the one produced by OpenShiftClientProducer (OpenShiftClient)
• BeanOverridesTest: A user is able to override the default OpenShiftClient with their own instance and producer method without providing further configurations or annotations.
  (requires that all of our producer methods are annotated with @DefaultBean. Requires our processor methods to remove one of the producers in case both extensions coexist.)

[quarkus-bot]

✔️ The latest workflow run for the pull request has completed successfully.

It should be safe to merge provided you have a look at the other checks in the summary.