[Kafka API] fix auth flags check (#18596)

Author: a-serebryanskiy

ydb/core/kafka_proxy/kafka_connection.cpp

@@ -101,7 +101,7 @@ class TKafkaConnection: public TActorBootstrapped<TKafkaConnection>, public TNet
 
     void Bootstrap() {
         Context->ConnectionId = SelfId();
-        Context->RequireAuthentication = NKikimr::AppData()->EnforceUserTokenRequirement;
+        Context->RequireAuthentication = NKikimr::AppData()->EnforceUserTokenRequirement || NKikimr::AppData()->PQConfig.GetRequireCredentialsInNewProtocol();
         // if no authentication required, then we can use local database as our target
         if (!Context->RequireAuthentication) {
             Context->DatabasePath = NKikimr::AppData()->TenantName;
@@ -452,7 +452,7 @@ class TKafkaConnection: public TActorBootstrapped<TKafkaConnection>, public TNet
             return;
         }
 
-        Context->RequireAuthentication = NKikimr::AppData()->EnforceUserTokenRequirement;
+        Context->RequireAuthentication = NKikimr::AppData()->EnforceUserTokenRequirement || NKikimr::AppData()->PQConfig.GetRequireCredentialsInNewProtocol();
         Context->UserToken = event->UserToken;
         Context->DatabasePath = event->DatabasePath;
         Context->AuthenticationStep = authStep;