Add alertDetailsUrl context variable to the ES query and Anomaly detection rules

[maryam-saeidi]

Summary

In the observability solution, we have a dedicated alert details page that can be included in the notifications using context.alertDetailsUrl. This ticket is about adding this action variable also to the following rules:

• Elasticsearch query rule
• Anomaly detection rule

Questions

1. Since these rules can also be created outside of the observability, is it OK to include these links for non-observability cases as well? The link will send the user to observability to a link similar to this: http://localhost:5601/eyr/app/observability/alerts/alert-uuid

[elasticmachine]

Pinging @elastic/obs-ux-management-team (Team:obs-ux-management)