[1688] use referene, rather than making a local copy, for a const vector.

src/bin/auth/query.cc

@@ -77,7 +77,7 @@ void
 Query::ResponseCreator::create(Message& response,
                                const vector<ConstRRsetPtr>& answers,
                                const vector<ConstRRsetPtr>& authorities,
-                               const vector<ConstRRsetPtr> additionals,
+                               const vector<ConstRRsetPtr>& additionals,
                                const bool dnssec)
 {
     // Inserter should be reset each time the query is reset, so should be

src/bin/auth/query.h

@@ -452,7 +452,7 @@ public:
             isc::dns::Message& message,
             const std::vector<isc::dns::ConstRRsetPtr>& answers_,
             const std::vector<isc::dns::ConstRRsetPtr>& authorities_,
-            const std::vector<isc::dns::ConstRRsetPtr> additionals_,
+            const std::vector<isc::dns::ConstRRsetPtr>& additionals_,
             const bool dnssec);
 
     private: