Only use Z-hop setting for the used extruders

Otherwise the unused extruders still influence the build volume.

cura/BuildVolume.py

@@ -442,7 +442,7 @@ class BuildVolume(SceneNode):
 
     def _updateExtraZClearance(self) -> None:
         extra_z = 0.0
-        extruders = ExtruderManager.getInstance().getMachineExtruders(self._global_container_stack.getId())
+        extruders = ExtruderManager.getInstance().getUsedExtruderStacks()
         use_extruders = False
         for extruder in extruders:
             if extruder.getProperty("retraction_hop_enabled", "value"):