message: gimbal integration tests: check the return value for arming, takeoff & offboard
diff: @@ -66,8 +66,11 @@ TEST_F(SitlTest, GimbalTakeoffAndMove)
  std::this_thread::sleep_for(std::chrono::seconds(1));
  }
  - action->arm();
  - action->takeoff();
  + Action::Result action_result = action->arm();
  + EXPECT_EQ(action_result, Action::Result::SUCCESS);
  +
  + action_result = action->takeoff();
  + EXPECT_EQ(action_result, Action::Result::SUCCESS);
  telemetry->set_rate_camera_attitude(10.0);
  @@ -112,8 +115,11 @@ TEST_F(SitlTest, GimbalROIOffboard)
  send_gimbal_roi_location(gimbal, position.latitude_deg + latitude_offset_deg,
  position.longitude_deg, position.absolute_altitude_m + 1.f);
  - action->arm();
  - action->takeoff();
  + Action::Result action_result = action->arm();
  + EXPECT_EQ(action_result, Action::Result::SUCCESS);
  +
  + action_result = action->takeoff();
  + EXPECT_EQ(action_result, Action::Result::SUCCESS);
  std::this_thread::sleep_for(std::chrono::seconds(5));
  @@ -124,7 +130,8 @@ TEST_F(SitlTest, GimbalROIOffboard)
  // Send it once before starting offboard, otherwise it will be rejected.
  offboard->set_velocity_ned({0.0f, 0.0f, 0.0f, 0.0f});
  - offboard->start();
  + Offboard::Result offboard_result = offboard->start();
  + EXPECT_EQ(offboard_result, Offboard::Result::SUCCESS);
  auto fly_straight = [&offboard](int step_count, float max_speed) {
  for (int i = 0; i < step_count; ++i) {
  