message: fix: assign different connection handle in HeartBeatMonitorTest
diff: @@ -202,7 +202,9 @@ TEST_F(HeartBeatMonitorTest, TwoSessionsElapsed) {
  session_connection_map_, session_connection_map_lock_)));
  const uint32_t kSession1 = conn->AddNewSession(kDefaultConnectionHandle);
  - const uint32_t kSession2 = conn->AddNewSession(kDefaultConnectionHandle);
  +
  + const transport_manager::ConnectionUID kAnotherConnectionHandle = 2;
  + const uint32_t kSession2 = conn->AddNewSession(kAnotherConnectionHandle);
  TestAsyncWaiter waiter;
  uint32_t times = 0;
  