openstack-operator's controlplane webhook doesn't execute telemetry validation. The code to execute most of the other service operator validations was added in this commit https://github.com/openstack-k8s-operators/openstack-operator/commit/c3916c9c0d7d18a4b8fdec85b2d8e62ccb013572 . telemetry-operator is missing there. Fixing this will be useful for our current work on cloudkitty as well 

Steps to reproduce

1. `oc edit oscp`
2. set `.spec.telemetry.aodhApiOverride.route.spec.tls.certificate: "something"`
3. set `.spec.telemetry.aodhApiOverride.route.spec.tls.termination: edge`
4. successfully save, even though this configuration should be invalid

Expected behavior

• telemetry validation is being executed in controlplane webhook - the same as other services
• The modification above is rejected, because `.spec.telemetry.aodhApiOverride.route.tls.key` is missing