Revert "Add additional safety check for extruder switching off in later layers"
Revert "Add additional safety check for extruder switching off in later layers"

This reverts commit bc82fd98c9080c119baf8ec796764bb731e3ddfc.

Contributes to issue CURA-2795.

Ultimaker/CuraEngine,alephobjects/CuraEngine,Ultimaker/CuraEngine,alephobjects/CuraEngine,alephobjects/CuraEngine,ROBO3D/CuraEngine,ROBO3D/CuraEngine,ROBO3D/CuraEngine