security: sign and verify new signed Interest format

refs #4804

Change-Id: Ib819edb977fa06c670b04185a0d730203c7d7fdb
diff --git a/tests/unit/security/validation-policy-config.t.cpp b/tests/unit/security/validation-policy-config.t.cpp
index 53f6778..e660598 100644
--- a/tests/unit/security/validation-policy-config.t.cpp
+++ b/tests/unit/security/validation-policy-config.t.cpp
@@ -56,6 +56,7 @@
   VALIDATE_FAILURE(d, "Empty policy should reject everything");
 
   Interest i("/Security/ValidationPolicyConfig/I");
+  i.setCanBePrefix(false);
   this->m_keyChain.sign(i, signingByIdentity(this->identity));
   VALIDATE_FAILURE(i, "Empty policy should reject everything");
 }
@@ -372,6 +373,9 @@
 
   using Packet = typename Policy::Packet;
   Packet unsignedPacket("/Security/ValidatorFixture/Sub1/Sub2/Packet");
+  // All of the packet types inputed to this test case template are Interests, so we can call
+  // setCanBePrefix
+  unsignedPacket.setCanBePrefix(false);
 
   Packet packet = unsignedPacket;
   VALIDATE_FAILURE(packet, "Unsigned");