message: [tf.data service] Add note not to change journal directory name.
diff: @@ -50,6 +50,7 @@ namespace data {
  namespace {
  // The name of the journal directory inside the dispatcher's working directory.
  +// This name is load-bearing; do not change.
  constexpr char kJournalDir[] = "tf_data_dispatcher_journal";
  // The name of the datasets directory inside the dispatcher's working directory.
  constexpr char kDatasetsDir[] = "datasets";
  