[BUG] Custom Scheduling for detections

Describe the bug

According to the documentation. It is possible to define a custom scheduling based on an analytic story tag.
Link to the wiki doc: https://github.com/splunk/security_content/wiki/4.2-%E2%80%90-Customize-to-Your-Environment

Since it doesn't seem to be possible to define a custom scheduling for each detection (which sounds way more intuitive), the only solution for having more than 1 scheduling per type of detection is to use that analytic stories tag matching.

However, when adding the same config explained in your wiki, contentctl does not validate since it's not expecting a tag field.

I've found some reference about deprecating this field in your code but then I don't see how is this feature currently implemented.

Summary:

Expected behavior

When trying to create a custom deployment config like this

name: Schedule Credential Dumping Daily
id: bc91a8cd-35e7-4bb2-6140-e756cc46f214
date: '2020-04-27'
description: Schedule Credential Dumping Daily with Email notification to the SOC
author: Jose Hernandez
scheduling:
cron_schedule: '0 0 * * *'
earliest_time: -1d@d
latest_time: -10m@m
schedule_window: auto
alert_action:
email:
message: Splunk Alert $name$ triggered %fields%
subject: Splunk Alert $name$
to: soc@splunk.com
tags:
analytics_story: Credential Dumping

Contentctl complains about having a non existing field called tags.
What should happen is that the detection that uses the analytic story called "Credential Dumping" should be using the custom deployment file with the same matching tag.

Screenshots

contentctl Version:

v5.0.0

Additional context

Add any other context about the problem here.

Start with contentctl's deployment configuration validation and compare its accepted fields with the linked wiki example, especially the tags.analytics_story field. Check how analytic-story tags are represented on detections and how deployment schedules are matched. Done means the documented configuration validates and applies its schedule to detections tagged "Credential Dumping", with coverage for the reported case.