[3.13] gh-75666: idlelib backport of iomenu change (GH-151958) (GH-152995) (#152996)

[3.14]gh-75666: idlelib backport of iomenu change (GH-151958) (GH-152995)
(cherry picked from commit 4413f32)

Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>

Author: miss-islington

Lib/idlelib/idle_test/test_iomenu.py

@@ -23,11 +23,10 @@ def setUpClass(cls):
         cls.root = Tk()
         cls.root.withdraw()
         cls.editwin = EditorWindow(root=cls.root)
-        cls.io = iomenu.IOBinding(cls.editwin)
+        cls.io = cls.editwin.io
 
     @classmethod
     def tearDownClass(cls):
-        cls.io.close()
         cls.editwin._close()
         del cls.editwin
         cls.root.update_idletasks()