widgets: ConfirmationView: Allow the widget to manage its own visibility

When the buttons are pressed then the widget should be dismissed. There
is no reason to make the caller handle that.

Signed-off-by: Daniel Thompson <daniel@redfelineninja.org.uk>

wasp/widgets.py

@@ -354,8 +354,10 @@ class ConfirmationView:
         )
 
         if is_yes_button_press:
+            self.active = False
             return True
         elif is_no_button_press:
+            self.active = False
             return False
         else:
             return None