Fix remaining references to instance_container._id

These must've slipped through the cracks.

Contributes to issue CURA-4243.

cura/Settings/GlobalStack.py

@@ -74,7 +74,7 @@ class GlobalStack(CuraContainerStack):
             return
 
         if any(item.getId() == extruder.id for item in self._extruders.values()):
-            Logger.log("w", "Extruder [%s] has already been added to this stack [%s]", extruder.id, self._id)
+            Logger.log("w", "Extruder [%s] has already been added to this stack [%s]", extruder.id, self.getId())
             return
 
         self._extruders[position] = extruder

plugins/3MFReader/ThreeMFWorkspaceReader.py

@@ -567,7 +567,7 @@ class ThreeMFWorkspaceReader(WorkspaceReader):
                         if old_extruder_id:
                             new_extruder_id = extruder_stack_id_map[old_extruder_id]
                             new_id = new_extruder_id + "_current_settings"
-                            instance_container._id = new_id
+                            instance_container.setMetaDataEntry("id", new_id)
                             instance_container.setName(new_id)
                             instance_container.setMetaDataEntry("extruder", new_extruder_id)
                             containers_to_add.append(instance_container)
@@ -576,7 +576,7 @@ class ThreeMFWorkspaceReader(WorkspaceReader):
                         if machine_id:
                             new_machine_id = self.getNewId(machine_id)
                             new_id = new_machine_id + "_current_settings"
-                            instance_container._id = new_id
+                            instance_container.setMetadataEntry("id", new_id)
                             instance_container.setName(new_id)
                             instance_container.setMetaDataEntry("machine", new_machine_id)
                             containers_to_add.append(instance_container)