Introduce element &error into edebug specification lists for macros

Introduce element &error into edebug specification lists for macros

This fixes bug #37540.

* lisp/emacs-lisp/edebug.el (top level): New entry for &error in alist used to
associate elements with their handling functions.
(edebug-match-&error): New function.
(nested-backquote-form): Use the new element &error to abort instrumentation
on encountering a three deep nesting of backquotes (without intervening
commas).

* doc/lispref/edebug.texi (Specification List): Add an entry for &error.

* etc/NEWS: Add an entry for &error.