tests: fix UDP multicast transport tests with IPv6

A valid scope id is always required on the multicast address

Change-Id: Ic676fcde0ee50daf75eb38c137e3cb917f43699f
diff --git a/tests/daemon/face/unicast-udp-transport-fixture.hpp b/tests/daemon/face/unicast-udp-transport-fixture.hpp
index e7fb76d..7ec4896 100644
--- a/tests/daemon/face/unicast-udp-transport-fixture.hpp
+++ b/tests/daemon/face/unicast-udp-transport-fixture.hpp
@@ -32,6 +32,7 @@
 #include "tests/test-common.hpp"
 #include "tests/daemon/limited-io.hpp"
 #include "tests/daemon/face/dummy-link-service.hpp"
+#include "tests/daemon/face/transport-test-common.hpp"
 
 namespace nfd::tests {
 
@@ -43,7 +44,7 @@
 {
 protected:
   void
-  initialize(ip::address address,
+  initialize(const shared_ptr<const ndn::net::NetworkInterface>&, const ip::address& address,
              ndn::nfd::FacePersistency persistency = ndn::nfd::FACE_PERSISTENCY_PERSISTENT)
   {
     udp::socket sock(g_io);
@@ -61,7 +62,7 @@
   }
 
   void
-  remoteConnect(ip::address address = ip::address_v4::loopback())
+  remoteConnect(const ip::address& address = ip::address_v4::loopback())
   {
     udp::endpoint remoteEp(address, 7070);
     remoteSocket.open(remoteEp.protocol());