Remove 'seen' debug aid

Terminal.Gui/ConsoleDrivers/CursesDriver/CursesDriver.cs

@@ -587,7 +587,6 @@ internal class CursesDriver : ConsoleDriver
     /// <inheritdoc />
     public override IAnsiResponseParser GetParser () => Parser;
 
-    private List<int> seen = new List<int> ();
     internal void ProcessInput ()
     {
         int wch;
@@ -601,8 +600,6 @@ internal class CursesDriver : ConsoleDriver
 
         var k = KeyCode.Null;
 
-        seen.Add (wch);
-
         if (code == Curses.KEY_CODE_YES)
         {
             while (code == Curses.KEY_CODE_YES && wch == Curses.KeyResize)