Add missing __slots__ to third-party packages (#15454)

stubs/psycopg2/psycopg2/_range.pyi

@@ -8,6 +8,7 @@ from psycopg2._psycopg import _type, connection, cursor
 _T_co = TypeVar("_T_co", covariant=True)
 
 class Range(Generic[_T_co]):
+    __slots__ = ("_lower", "_upper", "_bounds")
     def __init__(
         self, lower: _T_co | None = None, upper: _T_co | None = None, bounds: str = "[)", empty: bool = False
     ) -> None: ...

stubs/psycopg2/psycopg2/extras.pyi

@@ -71,6 +71,7 @@ class DictCursor(DictCursorBase):
     def __next__(self) -> DictRow: ...  # type: ignore[override]
 
 class DictRow(list[Any]):
+    __slots__ = ("_index",)
     def __init__(self, cursor) -> None: ...
     def __getitem__(self, x): ...
     def __setitem__(self, x, v) -> None: ...