Enforce abuse WHOIS contact for REAL registrars when adding TLDs

We do not enforce this for non-REAL registrars or in any environment other than UNITTEST or PRODUCTION. This is similar but separate to [] since we can add allowed TLDs in either location.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=239510275

java/google/registry/model/registrar/Registrar.java

@@ -561,6 +561,16 @@ public class Registrar extends ImmutableObject implements Buildable, Jsonifiable
         .collect(toImmutableSortedSet(CONTACT_EMAIL_COMPARATOR));
   }
 
+  /**
+   * Returns the {@link RegistrarContact} that is the WHOIS abuse contact for this registrar, or
+   * empty if one does not exist.
+   */
+  public Optional<RegistrarContact> getWhoisAbuseContact() {
+    return getContacts().stream()
+        .filter(RegistrarContact::getVisibleInDomainWhoisAsAbuse)
+        .findFirst();
+  }
+
   private Iterable<RegistrarContact> getContactsIterable() {
     return ofy().load().type(RegistrarContact.class).ancestor(Registrar.this);
   }