Function getNewsletterSubscribers

Returns Promise<
    {
        subscribers: {
            displayName?: string;
            id: WAJS.whatsapp.Wid;
            isContact?: boolean;
            isGroup?: boolean;
            isOnline?: boolean;
            isUser?: boolean;
            phoneNumber?: string;
            shortname?: string;
            state?: string;
            subscribeTime?: number;
            t: number;
        }[];
    },
>