fix(mypy): Cast Literal to type to please mypy

Author: ferdinandjarisch

src/gallia/pydantic_argparse/utils/pydantic.py

@@ -120,7 +120,7 @@ def _get_type(self, annotation: type | None) -> type | tuple[type | None, ...] |
         origin = get_origin(annotation)
 
         if origin is Literal or isinstance(origin, type) and issubclass(origin, Container):
-            return origin
+            return cast(type, origin)  # Cast to type to cover returning Literal
         elif origin is Union or origin is UnionType:
             args = get_args(annotation)
             types = [arg for arg in args if arg is not NoneType]