apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/api/AdminServiceAPI.java/AdminServiceAPI/deleteNamespace
class AdminServiceAPI:    public void deleteNamespace(Env env, String appId, String clusterName, String namespaceName, String operator) {
      restTemplate
          .delete(env, "apps/{appId}/clusters/{clusterName}/namespaces/{namespaceName}?operator={operator}", appId,
              clusterName,
              namespaceName, operator);
    }