import { Api } from "https://dotland.deno.dev/x/grammy@v1.20.2/mod.ts";
Use this method to clear the list of pinned messages in a 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. Returns True on success.
Parameters
Unique identifier for the target chat or username of the target supergroup (in the format @supergroupusername)
Optional AbortSignal
to cancel the request
Official reference: https://core.telegram.org/bots/api#unpinallforumtopicmessages