The PrintInformation test wasn't cleaning up after itself correclty. This
left some stuff behind that the other tests were using. Since this is bad (as at that point
tests can influence other tests), i've fixed that
We don't want to use it outside of the mapping. This mapping should be transparent.
We are still using it from our tests though but that's fine. Tests are allowed to touch private fields.
Contributes to issue CURA-6793.
The new lazy loading requests different functions from the registry so we need to mock that out.
Also fix the manual insertion of things into the lazy-loaded mapping.
Contributes to issue CURA-6793.
Because global_stack.extruders.values can be returned in any order, the configurations matching with the lists doesn't always give a result.
It happened to work on my computer with the test, but there is no guarantee of that.
This is probably also going wrong in other places. I don't think we should use the .extruders property anywhere really!
Contributes to issue CURA-6600.
