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