Some motor inputs don't work well in mock environment

[axelboc]

Originally described in #1429:

In the mock environment, I can't seem to get the step inputs of the following "motors" to work:

• Sample Vertical
• Sample Horizontal
• Focus

If I recall, those are actually abstract motors that control multiple physical motors, so perhaps it is a limitation of the mock environment?

Interestingly, if you pay close attention, when I press the arrows, the motor input sometimes receives a value that does not make sense whatsoever for a split millisecond (starting with 3 when pressing the up arrow, or -0. when pressing the down arrow) — it seems to overshoot before going back to the initial value +/- 0.1.

[beteva]

The difference between these three motors and the others is that the role in ui.yaml differs from the real motor name.
Could you, please, try to change the role in the ui.yaml to see if it changes

[marcus-oscarsson]

Perfect, I was just about to create this issue :)