Staging Canary: Monitor experimental Ruby 3.2 package roll out to gstg-cny

We plan to deploy a Ruby 3.2 package to gstg-cny before the production rollout.

Delivery: Ruby 3.2 rollout to .com and self-man... (gitlab-com/gl-infra&1377 - closed)

gitlab-com/gl-infra/production#18470 (closed)

This issue is to cover the dashboards and metrics we should monitor. Note for this rollout we are only interested in staging canary metrics in this issue.

We should record data as comments in this issue as we check each of the metrics/logs etc.

Key metrics to observe

Edited by Paul Phillips