Don't include text properties when making autoloads

* lisp/emacs-lisp/autoload.el (autoload-generate-file-autoloads):
Ignore text properties when finding autoload defs.  Otherwise,
autoload generation is less deterministic, as the exact format of the
generated autoloads depends on whether the files are visited in
Emacs.  (Bug#32395)

lisp/emacs-lisp/autoload.el

@@ -768,7 +768,7 @@ FILE's modification time."
                                      "define-erc-module"
                                      "define-erc-response-handler"
                                      "defun-rcirc-command"))))
-                    (push (match-string 2) defs))
+                    (push (match-string-no-properties 2) defs))
                             (forward-sexp 1)
                             (forward-line 1)))))))