Fix a failing unit test

Author: seratch

slack-api-client/src/test/java/test_locally/api/methods/FieldValidation_a_to_c_Test.java

@@ -492,6 +492,7 @@ public void conversations_commands() throws Exception {
                     "getTopic",
                     "getPurpose",
                     "getCreator",
+                    "getUpdated",
                     "getUnlinked",
                     "getSharedTeamIds",
                     "getPreviousNames",