pyright 1.1.396: error: Argument of type "None" cannot be assigned ...

[Andrei-Pozolotin]

starting with pyright 1.1.396, stubs such as:

# DocumentPy.xml
class Document(FreeCAD.PropertyContainer):
    def findObjects(self, Type: str = 'App::DocumentObject', Name: str = None, Label: str = None) -> list[FreeCADGui.DocumentObjectPy]:

with invocations like:

            group_list = this_doc.findObjects(
                Type=type_consts.App.DocumentObjectGroup, Name=group_name
            )

results in error:

error: Argument of type "None" cannot be assigned to parameter "Label" of type "str" in function "findObjects"
    "None" is not assignable to "str" (reportArgumentType)

since:

Label: str = None

is now expected to be instead:

Label: str|None = None