unfurl_links: false works with chat.postMessage but not with chat.scheduleMessage

Description

Specifying unfurl_links: false seems not working for scheduleMessage method, but it works fine for postMessage. I send a couple of links, and a result message becomes a bit messy if all the links get previews so I would like to prevent automatic links unfurling. It's worth mentioning that I run scheduleMessage in a cron job, and send time varies from a couple of minutes to 12 hours but the result is always the same.

Here is a Slack doc about unfurling

What type of issue is this? (place an x in one of the [ ])

• bug
• enhancement (feature request)
• question
• documentation related
• example code related
• testing related
• discussion

Requirements (place an x in each of the [ ])

• I've read and understood the Contributing guidelines and have done my best effort to follow them.
• I've read and agree to the Code of Conduct.
• I've searched for any related issues and avoided creating a duplicate issue.

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Bug Report

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Reproducible in:

package version: 3.8.1

node version: v14.17.1

OS version(s): MacOS 11.6, linux-based OS on remote server

Steps to reproduce:

1. Call chat.scheduleMessage method with unfurl_links: false param

Expected result:

The scheduled message will not be automatically unfurled after being sent to a user. The same way as if you specify unfurl_links: false for chat.postMessage

Actual result:

The scheduled message will be automatically unfurled after being sent to a user

Attachments:

The result message will be unfurled

      const response = await app.client.chat.scheduleMessage({
        channel: user.channel_id,
        post_at: timestamp,
        token: team.bot_token,
        blocks: [{
          type: 'section',
          text: {
            type: 'mrkdwn',
            text: `${welcomeMessage}\n${joinedSkills}`
          }
        }],
        text: welcomeMessage,
        unfurl_links: false,
        unfurl_media: false
      });

The result message will not be unfurled

      const response = await app.client.chat.postMessage({
        channel: user.channel_id,
        token: team.bot_token,
        blocks: [{
          type: 'section',
          text: {
            type: 'mrkdwn',
            text: `${welcomeMessage}\n${joinedSkills}`
          }
        }],
        text: welcomeMessage,
        unfurl_links: false,
        unfurl_media: false
      });

Interface of scheduleMessage arguments in typescript. It's the reason why I actually try to send this param

export interface ChatScheduleMessageArguments extends WebAPICallOptions, TokenOverridable {
    channel: string;
    text?: string;
    post_at: string | number;
    as_user?: boolean;
    attachments?: MessageAttachment[];
    blocks?: (KnownBlock | Block)[];
    link_names?: boolean;
    parse?: 'full' | 'none';
    reply_broadcast?: boolean;
    thread_ts?: string;
    unfurl_links?: boolean;
    unfurl_media?: boolean;
    team_id?: string;
}