* Merge Owner and Cluster ID into single value
* Remove aTLS from KMS, as it is no longer used for cluster external communication
* Update verify command to use cluster-id instead of unique-id flag
* Remove owner ID from init output
Signed-off-by: Daniel Weiße <dw@edgeless.systems>
AB#2074: Add configurable k8s version
Configurable version flow:
* cli config holds/validates k8sVersion
* InitCluster receive a k8sVersion arg
* InitCluster creates CM "k8s-version"
* kubeadm's InitConfiguration receives k8sVersion
* joinservice spec mounts/reads k8s-version CM
* joinservice supplies k8sVersion via JoinTicketResponse
Other changes:
* Remove unused test code (FakeK8SClient)
* move VersionConfig map to /internal/versions
* installk8sComponents is now a function instead of a method
