Retore the deployment probes.

Boxcutter is introducing phase progression status probes. One of these waits for the Deployment to be available before the revision can be said to be deployed successfully / available.

We'll need to update all OTE tests to ensure that the operator fixtures images post readiness and liveliness probe results to ensure revisions complete successfully. For the dummy operator, this can be done using the current upstream strategy that uses the httpd command to back the pod probe endpoints. But, we need to make sure httpd exists in the image. Otherwise, we could (at least in the short term) just remove the probes from the Deployment pod template spec for the dummy operator. However, we'll eventually want to exercise the Availability condition. And being able to manage it in the same way we are able to with the upstream strategy will be a requirement.