CVE-2023-1667:tests: Send a bit more to make sure rekey is completed

This was for some reason failing on CentOS 7 in 0.10 branch so bringing this to
the master too.

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Norbert Pocs <npocs@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>

Author: Jakuje

tests/client/torture_rekey.c

@@ -192,10 +192,11 @@ static void torture_rekey_send(void **state)
     rc = ssh_userauth_publickey_auto(s->ssh.session, NULL, NULL);
     assert_int_equal(rc, SSH_AUTH_SUCCESS);
 
-    /* send ignore packets of up to 1KB to trigger rekey */
+    /* send ignore packets of up to 1KB to trigger rekey. Send little bit more
+     * to make sure it completes with all different ciphers */
     memset(data, 0, sizeof(data));
     memset(data, 'A', 128);
-    for (i = 0; i < 16; i++) {
+    for (i = 0; i < KEX_RETRY; i++) {
         ssh_send_ignore(s->ssh.session, data);
         ssh_handle_packets(s->ssh.session, 50);
     }