Implementation Plan: Baseline Alarms for ECS Services (#2343)

* Implementation Plan: Baseline Alarms for ECS Services

* Clarify, de-duplicate, and add run book samples

* Edits; remove unnecessary alternative implementation

* Further edits for clarity

* Switch reviewers due to availability

* Add Elasticache mention.

Co-authored-by: Krystle Salazar <[email protected]>

* Fix dangling sentence

Co-authored-by: Krystle Salazar <[email protected]>

* Add downtime to terms and clarify usage in separate section

* Clarify alarm maintainer are assigned during only stabilisation

* Remove unclear "monitors" usage including `service-monitors` rename

* Fix typographical errors

Co-authored-by: Staci Mullins <[email protected]>
Co-authored-by: Madison Swain-Bowden <[email protected]>

* Add links to related incident reports to run books

* `runbook` -> `run book`

* Add link to issue for logs insights based metrics

* Clarify CloudWatch dashboard vis-a-vis other "monitoring" modules

* Add Madison's approval

* Wrap admonition text

Co-authored-by: Krystle Salazar <[email protected]>

* MSR as first point of response even for unstable alarms

* Update documentation/projects/proposals/monitoring/run_book_samples/stable_run_book_sample.md

Co-authored-by: Krystle Salazar <[email protected]>

* Update documentation/projects/proposals/monitoring/20230606_implementation_plan_ecs_alarms.md

Co-authored-by: Zack Krida <[email protected]>

* Add approvals

Co-authored-by: Zack Krida <[email protected]>
Co-authored-by: Staci Mullins <[email protected]>

* Fix linting errors

---------

Co-authored-by: Krystle Salazar <[email protected]>
Co-authored-by: Staci Mullins <[email protected]>
Co-authored-by: Madison Swain-Bowden <[email protected]>
Co-authored-by: Zack Krida <[email protected]>