bpo-35770: IDLE macosx deletes Options => Configure IDLE. (GH-11614)


It previously deleted Window => Zoom Height by mistake.
(Zoom Height is now on the Options menu).  On Mac, the settings
dialog is accessed via Preferences on the IDLE menu.
(cherry picked from commit 39ed289a3511d2e9bf0950a9d5dc53c8194f61b9)

Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>
diff --git a/Lib/idlelib/macosx.py b/Lib/idlelib/macosx.py
index 9be4ed2..d6a1b37 100644
--- a/Lib/idlelib/macosx.py
+++ b/Lib/idlelib/macosx.py
@@ -178,7 +178,7 @@
     del mainmenu.menudefs[-1][1][0:2]
     # Remove the 'Configure Idle' entry from the options menu, it is in the
     # application menu as 'Preferences'
-    del mainmenu.menudefs[-2][1][0]
+    del mainmenu.menudefs[-3][1][0:1]
     menubar = Menu(root)
     root.configure(menu=menubar)
     menudict = {}