[3.13] gh-141757: Comply with pickle protocol in test_reduce_5tuple (GH-141759) (GH-141783)

The 5th element of the __reduce__ tuple should be an iterator.
(cherry picked from commit 41b9ad5b38e913194a5cc88f0e7cfc096787b664)

Co-authored-by: Arseny Boykov <36469655+Bobronium@users.noreply.github.com>