enable circuit breaker for backup request

src/brpc/controller.cpp

@@ -260,6 +260,7 @@ void Controller::ResetPods() {
 Controller::Call::Call(Controller::Call* rhs)
     : nretry(rhs->nretry)
     , need_feedback(rhs->need_feedback)
+    , enable_circuit_breaker(rhs->enable_circuit_breaker)
     , peer_id(rhs->peer_id)
     , begin_time_us(rhs->begin_time_us)
     , sending_sock(rhs->sending_sock.release())