refactor: added type ignore for no checking mypy

Author: SepehrBazyar

ormar/relations/relation_proxy.py

@@ -61,7 +61,7 @@ def related_field_name(self) -> str:
 
         return self._related_field_name
 
-    def __getitem__(self, key: Union[int, slice]) -> "QuerysetProxy[T]":
+    def __getitem__(self, key: Union[int, slice]) -> "T":  # type: ignore
         """
         You can slice the results to desired number of parent models.