Revert "feat(Invite): add deletable getter (discordjs#3203)"

This reverts commit bf767ac.

src/structures/Invite.js

@@ -1,7 +1,6 @@
 'use strict';
 
 const { Endpoints } = require('../util/Constants');
-const Permissions = require('../util/Permissions');
 const Base = require('./Base');
 
 /**
@@ -92,18 +91,6 @@ class Invite extends Base {
     return this.createdTimestamp ? new Date(this.createdTimestamp) : null;
   }
 
-  /**
-   * Whether the invite is deletable by the client user
-   * @type {boolean}
-   * @readonly
-   */
-  get deletable() {
-    const guild = this.guild;
-    if (!guild || !this.client.guilds.has(guild.id)) return false;
-    return this.channel.permissionsFor(this.client.user).has(Permissions.FLAGS.MANAGE_CHANNELS, false) ||
-      guild.me.permissions.has(Permissions.FLAGS.MANAGE_GUILD);
-  }
-
   /**
    * The timestamp the invite will expire at
    * @type {?number}

typings/index.d.ts

@@ -615,8 +615,7 @@ declare module 'discord.js' {
 		constructor(client: Client, data: object);
 		public channel: GuildChannel;
 		public code: string;
-		public readonly deletable: boolean;
-		public readonly createdAt: Date | null;
+		public readonly createdAt: Date;
 		public createdTimestamp: number | null;
 		public readonly expiresAt: Date | null;
 		public readonly expiresTimestamp: number | null;