Add an example group dashboard
This adds an example dashboard for a single stage-group. It currently shows:
- Rails request rates for all types
- Error rates for all types
- Links to kibana filtering for the right feature categories
- Sidekiq job completions
- Sidekiq job failures.
https://dashboards.gitlab.net/dashboard/snapshot/ImQ03a0lrxRy6U1Rzx2Jz7QMkYKZACC4
As a PoC for gitlab-com/gl-infra/scalability#663
In a next iteration (gitlab-com/gl-infra/scalability#664) we're going to extract some of this out, so it's configurable and reusable for all stage groups.
Edited by Bob Van Landuyt