Use “control plane” terminology in Use minikube to Create a Cluster

[sftim]

This is a Clean Up Request

What would you like to be added
Change Use minikube to Create a Cluster to call the control plane a “control plane”, not a “master”.

Why is this needed
Kubernetes terms have changed:

Old term	New term
Minion	Node
Master	Control plane

…however https://kubernetes.io/docs/tutorials/kubernetes-basics/create-cluster/cluster-intro/ has not yet got that memo.

This work would be part of #21621
The term “master” is unhelpful when it has connotations of being paired with “slave”.

Comments
Note that the diagrams also need revising at the same time (if need be, this could be 2 separate PRs that merge together).

/language en
/wg naming
/kind cleanup

[jailton]

/assign

[kbhawkey]

/triage accepted