add default empty value for etc_hosts_localhosts_dict_target (#7567)

roles/kubernetes/preinstall/tasks/0090-etchosts.yml

@@ -66,7 +66,7 @@
     state: present
     backup: yes
     unsafe_writes: yes
-  loop: "{{ etc_hosts_localhosts_dict_target|dict2items }}"
+  loop: "{{ etc_hosts_localhosts_dict_target|default({})|dict2items }}"
 
 # gather facts to update ansible_fqdn
 - name: Update facts