Remove use of deprecated extruders property

Removes lots of warnings from the test log, since there the logger doesn't prevent creating multiple of those.

Done during Turbo Testing and Tooling.

tests/Settings/TestGlobalStack.py

@@ -1,4 +1,4 @@
-# Copyright (c) 2018 Ultimaker B.V.
+# Copyright (c) 2020 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
 import pytest #This module contains unit tests.
@@ -58,24 +58,24 @@ def test_addExtruder(global_stack):
     with unittest.mock.patch("cura.Settings.CuraContainerStack.DefinitionContainer", unittest.mock.MagicMock):
         global_stack.definition = mock_definition
 
-    assert len(global_stack.extruders) == 0
+    assert len(global_stack.extruderList) == 0
     first_extruder = unittest.mock.MagicMock()
     first_extruder.getMetaDataEntry = lambda key: 0 if key == "position" else None
     with unittest.mock.patch("cura.Settings.CuraContainerStack.DefinitionContainer", unittest.mock.MagicMock):
         global_stack.addExtruder(first_extruder)
-    assert len(global_stack.extruders) == 1
-    assert global_stack.extruders[0] == first_extruder
+    assert len(global_stack.extruderList) == 1
+    assert global_stack.extruderList[0] == first_extruder
     second_extruder = unittest.mock.MagicMock()
     second_extruder.getMetaDataEntry = lambda key: 1 if key == "position" else None
     with unittest.mock.patch("cura.Settings.CuraContainerStack.DefinitionContainer", unittest.mock.MagicMock):
         global_stack.addExtruder(second_extruder)
-    assert len(global_stack.extruders) == 2
-    assert global_stack.extruders[1] == second_extruder
+    assert len(global_stack.extruderList) == 2
+    assert global_stack.extruderList[1] == second_extruder
     # Disabled for now for Custom FDM Printer
     # with unittest.mock.patch("cura.Settings.CuraContainerStack.DefinitionContainer", unittest.mock.MagicMock):
     #     with pytest.raises(TooManyExtrudersError): #Should be limited to 2 extruders because of machine_extruder_count.
     #         global_stack.addExtruder(unittest.mock.MagicMock())
-    assert len(global_stack.extruders) == 2 #Didn't add the faulty extruder.
+    assert len(global_stack.extruderList) == 2  # Didn't add the faulty extruder.
 
 
 #Tests setting user changes profiles to invalid containers.