message: offboard_velocity: fix expected result for offboard->is_active()
diff: @@ -70,7 +70,7 @@ TEST_F(SitlTest, OffboardVelocityNED)
  // This needs some time to propagate.
  std::this_thread::sleep_for(std::chrono::seconds(2));
  // Now it should be inactive.
  - EXPECT_TRUE(offboard->is_active());
  + EXPECT_FALSE(offboard->is_active());
  // So we start it yet again.
  offboard_result = offboard->start();
  