[synthetics] Update monitor status rule docs

[colleenmcginnis]

Description

The Synthetics monitor status rule type was improved in elastic/kibana#186585. This PR makes a few updates to the Create a monitor status rule doc including:

• Marking the Uptime rule as deprecated and making it clear that the Synthetics rule is the right choice moving forward.
• Fully documenting the Synthetics monitor status rule type with details on the available filters, conditions, action types, and action variables.
• Documenting how users who have an existing Uptime rule that they are using for their Synthetics monitors can replace the Uptime rule with the Synthetics rule.
  • @shahzad31 @paulb-elastic I'm not sure if this section (preview) is what you had in mind. I'm not sure there's a 1:1 comparison for everything included in the Uptime rule unless I'm misunderstanding. For example, I don't think you can recreate the Uptime rule's availability condition exactly using the new Synthetics rule conditions (would you use a synthetics SLI instead?). Let me know if I'm missing something or if there's a different way we should approach this.

Note: I documented the Uptime and Synthetics rules on the same page titled "Create a monitor status rule" because the "Alerts and rules" dropdown in both the Uptime app and Synthetics UI uses the language "Monitor status rule", but I could be persuaded to document them separately. Either way, starting in 9.0.0, I imagine the Uptime content on this page will go away.

Documentation sets edited in this PR

Check all that apply.

• Stateful (docs/en/observability/*)
• Serverless (docs/en/serverless/*)
• Integrations Developer Guide (docs/en/integrations/*)
• None of the above

Related issue

Closes #4164
Closes #4337

Checklist

• Product/Engineering Review
• Writer Review

Follow-up tasks

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• This PR does not need to be ported to another doc set because:
  • The concepts in this PR only apply to one doc set (serverless or stateful)
  • The PR contains edits to both doc sets (serverless and stateful)
• This PR needs to be ported to another doc set:
  • Port to stateful docs: <link to PR or tracking issue>
  • Port to serverless docs: <link to PR or tracking issue>

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[paulb-elastic]

I've not had a chance to look through this fully, but a couple of comments:

starting in 9.0.0, I imagine the Uptime content on this page will go away

Uptime is not being removed now in 9.0.0. It's still deprecated, but won't be removed until a later date (the release note was updated recently to reflect that change).

This deprecated content: whilst it's true that Uptime is deprecated (and as such, the corresponding rule), is this section clear that Uptime is deprecated and the suggestion is to use Synthetics as a whole solution (specifically, is there a chance it could be misread and people think they should use the Synthetics rule if still using Uptime)?

[shahzad31]

In PR preview, Monitor status rule still leads me to Uptime monitor status rule docs , i will recommend replacing that link with synthetics status alert !!

[shahzad31]

@colleenmcginnis we don't allow know creating availability alert from status rules, it doesn't make sense as far as i can understand. if you want you can mention Synthetics Availability SLI indicator, that's more suited for that kind of scenerio, where user want to get alerted on availability. So user looking for availability alert can learn about Synthetics Availability SLI indicator.

[colleenmcginnis]

In PR preview, Monitor status rule still leads me to Uptime monitor status rule docs , i will recommend replacing that link with synthetics status alert !!

You'll need to look at this link (master instead of current): https://observability-docs_bk_4345.docs-preview.app.elstc.co/guide/en/observability/master/monitor-status-alert.html. (Then we can backport to publish to other branches.)

[shahzad31]

LGTM , other than if we want to leave a comment about availability condition being replaced with Synthetics Availability SLI !!

[bmorelli25]

Did you mean to duplicate this on this page?

[bmorelli25]

@\reviewers it looks like there's still a question to be answered here