use new test headerfile

src/bin/auth/tests/auth_srv_unittest.cc

@@ -34,6 +34,7 @@
 #include <auth/statistics.h>
 
 #include <dns/tests/unittest_util.h>
+#include <testutils/dnsmessage_test.h>
 #include <testutils/srv_test.h>
 
 using namespace std;