Increase the version of the CuraContainer stack

Since we added a new layer to it, it's version is one level higher (*DING*)

CURA-6534

cura/Settings/CuraContainerStack.py

@@ -37,6 +37,8 @@ from . import Exceptions
 #   This also means that operations on the stack that modifies the container ordering is prohibited and
 #   will raise an exception.
 class CuraContainerStack(ContainerStack):
+    Version = 5  # type: int
+
     def __init__(self, container_id: str) -> None:
         super().__init__(container_id)