fix Var.contains pyi (#3663)

reflex/vars.pyi

@@ -118,7 +118,7 @@ class Var:
     def __or__(self, other: Var) -> Var: ...
     def __ror__(self, other: Var) -> Var: ...
     def __contains__(self, _: Any) -> Var: ...
-    def contains(self, other: Any) -> Var: ...
+    def contains(self, other: Any, field: Union[Var, None] = None) -> Var: ...
     def reverse(self) -> Var: ...
     def foreach(self, fn: Callable) -> Var: ...
     @classmethod