Refactor: var kube_override_hostname only reserve in kubespray-defaults

Signed-off-by: ChengHao Yang <17496418+tico88612@users.noreply.github.com>

roles/kubernetes/kubeadm/defaults/main.yml

@@ -6,10 +6,3 @@ kubeadm_join_timeout: 120s
 
 # Enable kubeadm file discovery if anonymous access has been removed
 kubeadm_use_file_discovery: "{{ remove_anonymous_access }}"
-
-# If non-empty, will use this string as identification instead of the actual hostname
-kube_override_hostname: >-
-  {%- if cloud_provider is defined -%}
-  {%- else -%}
-  {{ inventory_hostname }}
-  {%- endif -%}