JSON: fix: better max infill_sparse_thickness (CURA-1255)
JSON: fix: better max infill_sparse_thickness (CURA-1255)

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