Replace kube-master with kube_control_plane (#7256)

This replaces kube-master with kube_control_plane because of [1]:

  The Kubernetes project is moving away from wording that is
  considered offensive. A new working group WG Naming was created
  to track this work, and the word "master" was declared as offensive.
  A proposal was formalized for replacing the word "master" with
  "control plane". This means it should be removed from source code,
  documentation, and user-facing configuration from Kubernetes and
  its sub-projects.

NOTE: The reason why this changes it to kube_control_plane not
      kube-control-plane is for valid group names on ansible.

[1]: https://github.com/kubernetes/enhancements/blob/master/keps/sig-cluster-lifecycle/kubeadm/2067-rename-master-label-taint/README.md#motivation

roles/network_plugin/cilium/tasks/install.yml

@@ -39,7 +39,7 @@
     - {name: cilium, file: cilium-sa.yml, type: sa}
   register: cilium_node_manifests
   when:
-    - inventory_hostname in groups['kube-master']
+    - inventory_hostname in groups['kube_control_plane']
 
 - name: Cilium | Enable portmap addon
   template:

roles/network_plugin/cilium/tasks/main.yml

@@ -1,4 +1,4 @@
 ---
 - import_tasks: check.yml
 
-- include_tasks: install.yml
+- include_tasks: install.yml