Remove unnecessary generic type arguments

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=175155365

java/google/registry/rdap/RdapEntityAction.java

@@ -24,7 +24,6 @@ import com.google.common.primitives.Longs;
 import com.google.re2j.Pattern;
 import com.googlecode.objectify.Key;
 import google.registry.model.contact.ContactResource;
-import google.registry.model.domain.DesignatedContact;
 import google.registry.model.registrar.Registrar;
 import google.registry.rdap.RdapJsonFormatter.OutputDataType;
 import google.registry.rdap.RdapMetrics.EndpointType;
@@ -95,7 +94,7 @@ public class RdapEntityAction extends RdapActionBase {
         return rdapJsonFormatter.makeRdapJsonForContact(
             contactResource,
             true,
-            Optional.<DesignatedContact.Type>empty(),
+            Optional.empty(),
             fullServletPath,
             rdapWhoisServer,
             now,