Add a horizontal line at the end of the graphic menu

This is in line with the old behavior and the UI of TextMenu.

Bug: 121280655
Test: check the menu
Change-Id: I4b82b93187b2d02cfe5b31a9a8fb621d10dd5d8a
diff --git a/screen_ui.cpp b/screen_ui.cpp
index 5756054..7fa41c4 100644
--- a/screen_ui.cpp
+++ b/screen_ui.cpp
@@ -252,6 +252,7 @@
 
     draw_funcs_.SetColor(UIElement::MENU);
   }
+  offset += draw_funcs_.DrawHorizontalRule(y + offset);
 
   return offset;
 }