Update array2d.pyi

include/typings/array2d.pyi

@@ -27,7 +27,7 @@ class array2d(Generic[T]):
     def __setitem__(self, index: tuple[slice, slice], value: int | float | str | bool | None | 'array2d[T]'): ...
 
     def __len__(self) -> int: ...
-    def __iter__(self) -> Iterator[T]: ...
+    def __iter__(self) -> Iterator[tuple[int, int, T]]: ...
     def __eq__(self, other: 'array2d') -> bool: ...
     def __ne__(self, other: 'array2d') -> bool: ...
     def __repr__(self): ...