Fix `List_Append` description, list is extracted at TOS1[-i] (GH-21465)

diff --git a/Doc/library/dis.rst b/Doc/library/dis.rst
index f871ec4..d0307bd 100644
--- a/Doc/library/dis.rst
+++ b/Doc/library/dis.rst
@@ -640,7 +640,7 @@
 
 .. opcode:: LIST_APPEND (i)
 
-   Calls ``list.append(TOS[-i], TOS)``.  Used to implement list comprehensions.
+   Calls ``list.append(TOS1[-i], TOS)``.  Used to implement list comprehensions.
 
 
 .. opcode:: MAP_ADD (i)