This adds a `container_cpu_cfs_throttled_seconds_total:labeled`
variant of the `container_cpu_cfs_throttled_seconds_total` that
includes the `tier`, `type` and `stage` labels.

This will allow us to use these metrics in saturation points for
capacity planning.

For
https://gitlab.com/gitlab-com/gl-infra/scalability/-/issues/2724#note_1723377089
and https://gitlab.com/groups/gitlab-com/gl-infra/-/epics/946