Add FollowDetail type for FollowEvent

[nottyo]

To add FollowDetail object type to the FollowEvent type

Ref: https://developers.line.biz/en/reference/messaging-api/#follow-event

[CLAassistant]

All committers have signed the CLA.

[Yang-33]

how about using

• line-bot-sdk-nodejs/lib/webhook/model/followEvent.ts

  Lines 24 to 35 in 4da15ba

  	export type FollowEvent = EventBase & {
  	type: "follow";
  	/**
  	* Reply token used to send reply message to this event
  	*/
  	replyToken: string /**/;
  	/**
  	*/
  	follow: FollowDetail /**/;
  	};
  	export namespace FollowEvent {}

• line-bot-sdk-nodejs/lib/webhook/model/followDetail.ts

  Lines 13 to 18 in 4da15ba

  	export type FollowDetail = {
  	/**
  	* Whether a user has added your LINE Official Account as a friend or unblocked.
  	*/
  	isUnblocked: boolean /**/;
  	};

?

[nottyo]

Yeah, it's usable but the type defined in the lib/types still not up to date. Mostly people reference the type definition from this file, so should we update it as well ?

I mean we usually import the type like this

import { FollowEvent } from '@line/bot-sdk';

which is not up to date yet.

rather than

import { FollowEvent } from '@line/bot-sdk/dist/webhook/api';