chore: fix unit tests

Author: alter-mage

src/test/java/com/aws/greengrass/tes/TokenExchangeServiceTest.java

@@ -202,13 +202,7 @@ void GIVEN_token_exchange_service_WHEN_started_with_empty_role_alias_THEN_server
         // set mock for port topic
         Topic portTopic = mock(Topic.class);
         when(portTopic.dflt(anyInt())).thenReturn(portTopic);
-        when(portTopic.subscribe(any())).thenAnswer((a) -> {
-            ((Subscriber) a.getArgument(0)).published(WhatHappened.initialized, portTopic);
-            return null;
-        });
-        when(portTopic.getOnce()).thenReturn(8080);
-
-
+        
         when(config.lookup(CONFIGURATION_CONFIG_KEY, PORT_TOPIC)).thenReturn(portTopic);
         when(configuration.lookup(SERVICES_NAMESPACE_TOPIC, DEFAULT_NUCLEUS_COMPONENT_NAME, CONFIGURATION_CONFIG_KEY,
                 IOT_ROLE_ALIAS_TOPIC)).thenReturn(roleTopic);