apollo-mockserver/src/main/java/com/ctrip/framework/apollo/mockserver/EmbeddedApollo.java/EmbeddedApollo/mockLongPollBody
class EmbeddedApollo:  private String mockLongPollBody(String notificationsStr) {
    List<ApolloConfigNotification> oldNotifications = GSON.fromJson(notificationsStr, notificationType);
    List<ApolloConfigNotification> newNotifications = new ArrayList<>();
    for (ApolloConfigNotification notification : oldNotifications) {
      newNotifications
          .add(new ApolloConfigNotification(notification.getNamespaceName(), notification.getNotificationId() + 1));
    }
    return GSON.toJson(newNotifications);
  }