Update qtbot.py

Author: nicoddemus

src/pytestqt/qtbot.py

@@ -11,12 +11,12 @@
     Literal,
     Optional,
     Any,
-    Self,
     Type,
     TypeAlias,
     cast,
 )
 from pathlib import Path
+from typing_extensions import Self
 
 from pytestqt.exceptions import TimeoutError, ScreenshotError
 from pytestqt.qt_compat import qt_api