Add Zoekt admin APIs and chatops commands for enabling indexing and retriggering indexing
In gitlab-com/gl-infra/production#8622 (closed) we have to manually enable indexing via the Rails console. This causes a lot of delays because we need a C2
change request which requires lots of infra approvals and then we need to schedule time with an SRE to do the work. We will eventually start to roll out to many more groups so having a way to do it from ChatOps would be ideal. Chatops uses the API so we first need to add it to the GitLab API.
The GitLab API changes will also serve as a way to enable it for self-managed customers at some point in the future so it seems like a logical next step anyway as our existing approach is very manual (from the rails console).
Eventually we'll start expanding the rollout to percentages of groups at a time so at that point we may also want to add that to chatops as well.