On deployment failure, automatically roll back to the previous revision.

When Runway detects an elevated rate of 5xx errors, the deployment process fails, but leaving the service in the degraded state. In this case, Runway should revert to the previously deployed revision.

This won't help with problems in the infrastructure, e.g. faulty IAM policies, but we have other mechanisms to detect these kind of issues during runwayctl development.

Status 2024-07-31

MR to roll back deployment on monitoring failure runwayctl!527 (merged) is under review.