Refactor out creation of server TRIDs so they can be tested

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152837185

javatests/google/registry/model/contact/ContactResourceTest.java

@@ -110,7 +110,7 @@ public class ContactResourceTest extends EntityTestCase {
                         Key.create(BillingEvent.OneTime.class, 1)))
                 .setTransferRequestTime(clock.nowUtc())
                 .setTransferStatus(TransferStatus.SERVER_APPROVED)
-                .setTransferRequestTrid(Trid.create("client trid"))
+                .setTransferRequestTrid(Trid.create("client-trid", "server-trid"))
                 .build())
             .build()));
   }