Add tests for setMaterialById
Add tests for setMaterialById

One for when the ID exists, and one for when it doesn't.

Contributes to issue CURA-3497.

Curahelper/Cura,fieldOfView/Cura,Curahelper/Cura,ynotstartups/Wanhao,hmflash/Cura,hmflash/Cura,fieldOfView/Cura,ynotstartups/Wanhao