Refactor Guava functional methods to use lambdas

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=177027488

java/google/registry/rdap/RdapDomainSearchAction.java

@@ -460,7 +460,7 @@ public class RdapDomainSearchAction extends RdapActionBase {
       }
       Streams.stream(query)
           .filter(domain -> isAuthorized(domain, now))
-          .forEach(domain -> domainSetBuilder.add(domain));
+          .forEach(domainSetBuilder::add);
     }
     List<DomainResource> domains = domainSetBuilder.build().asList();
     metricInformationBuilder.setNumHostsRetrieved(numHostKeysSearched);