feat(AllowedMentions): add support for MessageOptions#allowedMe… (#3893)

* feat(Allowed Mentions): Add support for new Allowed Mentions message options

* fix(docs): Update JSDoc for feature

* fix(apimessage): translate the propery into snake_case

* fix(typings): message mention options should be optional

* fix(docs): jsdoc typings for MessageMentionOptions

* fix(mentions): use Resolvables for MessageMentionOptions

* fix(docs): typedef for MessageMentionTypes

* Update typings/index.d.ts

Co-Authored-By: Sugden <28943913+NotSugden@users.noreply.github.com>

* fix(mentions): drop support for Resolvables

* fix(AllowedMentions): remove the whole resolve function

* fix(docs): revert change to Resolvables

Co-authored-by: Sugden <28943913+NotSugden@users.noreply.github.com>

src/structures/APIMessage.js

@@ -184,6 +184,7 @@ class APIMessage {
       embeds,
       username,
       avatar_url: avatarURL,
+      allowed_mentions: this.options.allowedMentions,
       flags,
     };
     return this;