Add new sla_weighted_v3 SLA to metrics.
Rather than notify everyone involved in #2299 (closed), I'm opening a separate issue.
Andrew suggested the following:
@stejacks-gitlab it's important that we track the old SLA score alongside the new one, for a period of at least a few months. We have a way of doing this: through the sla_type label on sla:gitlab:score: thanos query Some discussion on this: https://docs.google.com/document/d/1Zk3qgbn8iDyJRq0i5C5LPBgEopY6o1tpYEKfdNfA9Bg/edit#bookmark=id.oxwk27afhknw It might be worth starting to record the new SLA rules now, with sla_type="weighted_v3" so we can compare, before and after the switch.
We're currently measuring SLA here -- https://gitlab.com/gitlab-com/runbooks/-/blob/master/thanos-rules-jsonnet/sla-rules.jsonnet, and it's fairly simple to add a second label and have it correctly autogenerate a second set of labels.
I'm just not sure how to override the sidekiq 0 weight, so I'm opening this to solicit opinions from @reprazent.