prep_kubeadm_images: parse repo and tag (#4976) (#4977)

roles/download/tasks/prep_kubeadm_images.yml

@@ -57,8 +57,8 @@
       value:
         enabled: true
         container: true
-        repo: "{{ item.split(':')[0] }}"
-        tag: "{{ item.split(':')[1] }}"
+        repo: "{{ item | regex_replace('^(.*):.*$','\\1') }}"
+        tag: "{{ item | regex_replace('^.*:(.*)$','\\1') }}"
         groups: k8s-cluster
   loop: "{{ kubeadm_images_list | flatten(levels=1) }}"
   register: kubeadm_images_cooked