Conform to RDAP Technical Implementation Guide

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=251864499

java/google/registry/rdap/RdapMetrics.java

@@ -298,6 +298,7 @@ public class RdapMetrics {
           .setSearchType(SearchType.NONE)
           .setWildcardType(WildcardType.INVALID)
           .setPrefixLength(0)
+          .setRegistrarSpecified(false)
           .setIncompletenessWarningType(IncompletenessWarningType.COMPLETE);
     }
   }