Revert "Fix for unknown 'kubernetes.io' or 'k8s.io' labels specified with --node-labels (#4320)" (#4553)

This reverts commit 586ad89d50.

roles/kubernetes/master/templates/kubeadm-config.v1beta1.yaml.j2

@@ -10,7 +10,7 @@ nodeRegistration:
 {% if inventory_hostname in groups['kube-master'] and inventory_hostname not in groups['kube-node'] %}
   taints:
   - effect: NoSchedule
-    key: node.kubernetes.io/master
+    key: node-role.kubernetes.io/master
 {% endif %}
 {% if container_manager == 'crio' %}
   criSocket: /var/run/crio/crio.sock