Check "require-cookie yes;" triggers TCP fallback on no cookie

bin/tests/system/cookie/ns7/from-no-cookie-server.example.db

@@ -0,0 +1,14 @@
+; Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+;
+; SPDX-License-Identifier: MPL-2.0
+;
+; This Source Code Form is subject to the terms of the Mozilla Public
+; License, v. 2.0.  If a copy of the MPL was not distributed with this
+; file, you can obtain one at https://mozilla.org/MPL/2.0/.
+;
+; See the COPYRIGHT file distributed with this work for additional
+; information regarding copyright ownership.
+
+@	SOA	ns7 hostmaster.isc.org. 1 600 600 1200 600
+@ 	NS	ns7
+ns7 	A	10.53.0.7