unpinAllGeneralForumTopicMessages(chatId, form = {}) {
    form.chat_id = chatId;
    return this._request('unhideGeneralForumTopic', { form });
  }
Use this method to clear the list of pinned messages in a General forum topic.
The bot must be an administrator in the chat for this to work and must have the can_pin_messages administrator right in the supergroup.

@param {Number|String} chatId Unique identifier for the target group or username of the target supergroup (in the format @supergroupusername)
@param {Object} [options] Additional Telegram query options
@return {Promise} True on success
@see https://core.telegram.org/bots/api#unpinallgeneralforumtopicmessages