Fix kubeadm upload certs with when condition (#4659)

* Fix kubeadm upload certs with when condition

Change-Id: I916dd2375b71eea2386047c7f185a2f8361f7a61

* Update kubeadm-secondary-experimental.yml

roles/kubernetes/master/tasks/kubeadm-secondary-experimental.yml

@@ -34,9 +34,9 @@
     {% if kubeadm_certificate_key is defined %}
     --certificate-key={{ kubeadm_certificate_key }}
     {% endif %}
-  run_once: yes
   register: kubeadm_upload_cert
-  delegate_to: "{{ groups['kube-master'][0] }}"
+  when:
+    - inventory_hostname == groups['kube-master']|first
 
 - name: Parse certificate key if not set
   set_fact: