Fix positioning of exit confirmation (compatibilitiy with latest prompt_toolkit).

Author: jonathanslenders

src/ptpython/layout.py

@@ -694,7 +694,8 @@ def menu_position() -> int | None:
                                         ),
                                         Float(
                                             left=2,
-                                            bottom=1,
+                                            top=2,
+                                            height=3,
                                             content=self.exit_confirmation,
                                         ),
                                         Float(