Optional[customOptional[unknownOptionalendpointsSubnet ID where control plane instances will be located.
Version is desired Kubernetes version of the cluster. For now only acceptable format is
MAJOR.MINOR like "1.31". Option for patch version update will be added later.
Number of instances in etcd cluster. 3 by default. Control plane with
etcd_cluster_size: 3called "Highly Available" ("HA"), because it's Kubernetes API will be available despite a failure of one control plane instance.