feat: add alert escalation policy as part of the check/config

[ferrandiaz]

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Affected Components

• CLI
• Create CLI
• Test
• Docs
• Examples
• Other

Notes for the Reviewer

Alert Escalation policy can be defined either on the check, the check group or the checkly config file

Resolves #901

[ferrandiaz]

I see one test failing due to Unable to run checks: \"checkRunJobs[0].useGlobalAlertSettings\" is not allowed , I suspect this is going to be fixed the moment I merge this other PR https://github.com/checkly/checkly-backend/pull/5075

[umutuzgur]

@tnolet what do you think about this? Basically we set useGlobalAlertSettings to true if alertSettings doesn't exist and vice versa

[tnolet]

@umutuzgur @ferrandiaz hmmmm, feels a bit iffy / hidden magic. Not sure if we have a great alternative.

[clample]

Just my 2 cents, but I think it's nice. As a user, I think that it would be confusing if I passed alertSettings, but they weren't actually applied because I need to also explicitly set useGlobalAlertSettings. I'm not sure there's a case in the CLI were I would pass alertSettings but not want it to actually be used.

[tnolet]

@clample yes, I agree. This seems to be the best UX. @umutuzgur @ferrandiaz let's go with this.