fix: add clusterDomain in values

deploy/charts/emqx/templates/configmap.yaml

@@ -16,9 +16,9 @@ data:
   EMQX_CLUSTER__K8S__SERVICE_NAME:  {{ include "emqx.fullname" . }}-headless
   EMQX_CLUSTER__K8S__NAMESPACE: {{ .Release.Namespace }}
   EMQX_CLUSTER__K8S__ADDRESS_TYPE: "hostname"
-  EMQX_CLUSTER__K8S__SUFFIX: "svc.cluster.local"
+  EMQX_CLUSTER__K8S__SUFFIX: "svc.{{ .Values.clusterDomain }}"
   {{- else if eq (.Values.emqxConfig.EMQX_CLUSTER__DISCOVERY_STRATEGY)  "dns"  }}
-  EMQX_CLUSTER__DNS__NAME: "{{  include "emqx.fullname" . }}-headless.{{ .Release.Namespace }}.svc.cluster.local"
+  EMQX_CLUSTER__DNS__NAME: "{{  include "emqx.fullname" . }}-headless.{{ .Release.Namespace }}.svc.{{ .Values.clusterDomain }}"
   EMQX_CLUSTER__DNS__RECORD_TYPE: "srv"
   {{- end -}}
   {{- range $index, $value := .Values.emqxConfig }}