Fix check for has_variants & has_materials
Fix check for has_variants & has_materials

These are defined as bool values instead of strings in UM2+ definitions, so I would expect other machine definitions (including jedi) also use bools.

CURA-333

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