Add missing velocity state in the system test_component

hardware_interface_testing/test/test_components/test_system.cpp

@@ -88,6 +88,12 @@ class TestSystem : public SystemInterface
  {
  return return_type::DEACTIVATE;
  }
+ // The next line is for the testing purposes. We need value to be changed to
+ // be sure that the feedback from hardware to controllers in the chain is
+ // working as it should. This makes value checks clearer and confirms there
+ // is no "state = command" line or some other mixture of interfaces
+ // somewhere in the test stack.
+ velocity_state_[0] = velocity_command_[0] / 2.0;
  return return_type::OK;
  }