message: Fix in crash in GlobalNotifier
diff: @@ -278,8 +278,8 @@ util::Optional<GlobalNotifier::ChangeNotification> GlobalNotifier::next_changed_
  }
  auto realm = next->coordinator->get_realm();
  - TransactionRef transaction = Realm::Internal::get_transaction_ref(*realm);
  - auto old_version = transaction->get_version_of_current_transaction();
  + auto& transaction = Realm::Internal::get_transaction(*realm);
  + auto old_version = transaction.get_version_of_current_transaction();
  return ChangeNotification(m_impl, next->virtual_path, next->realm_id,
  next->coordinator->get_config(),
  old_version, next->versions.front());
  