Prevent erase_when_done affecting full screen apps

Author: joouha

Diff for: src/prompt_toolkit/application/application.py

@@ -530,7 +530,7 @@ def run_in_context() -> None:
                 self.before_render.fire()
 
                 if render_as_done:
-                    if self.erase_when_done:
+                    if self.erase_when_done and not self.full_screen:
                         self.renderer.erase()
                     else:
                         # Draw in 'done' state and reset renderer.