RDAP: Remove port43 element from JSON output

According to Gustavo Lozano of ICANN: "In the case of the RDAP profile (gTLD space), the “port43” element is not expected to be used, because Whois/43 tcp will be deprecated in the future." So it sounds like we should not include the port43 element for the moment.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=130017966

javatests/google/registry/rdap/RdapNameserverActionTest.java

@@ -76,7 +76,7 @@ public class RdapNameserverActionTest {
     action.response = response;
     action.requestPath = RdapNameserverAction.PATH.concat(input);
     action.rdapLinkBase = "https://example.tld/rdap/";
-    action.rdapWhoisServer = "whois.example.tld";
+    action.rdapWhoisServer = null;
     return action;
   }
 
@@ -121,9 +121,6 @@ public class RdapNameserverActionTest {
       if (!map.containsKey("rdapConformance")) {
         builder.put("rdapConformance", ImmutableList.of("rdap_level_0"));
       }
-      if (!map.containsKey("port43")) {
-        builder.put("port43", "whois.example.tld");
-      }
       if (!map.containsKey("notices")) {
         RdapTestHelper.addTermsOfServiceNotice(builder, "https://example.tld/rdap/");
       }