[Feature flag] Rollout of api_commits_without_count

What

Remove the :api_commits_without_count feature flag ...

Owners

• Team: ~"team::Scalability"
• Most appropriate slack channel to reach out to: #g_scalability
• Best individual to reach out to: @reprazent

Expectations

What are we expecting to happen?

We expect the X-Total and X-Total-Pages headers not to be present in the commits API

What might happen if this goes wrong?

We keep the extra gitaly call?

What can we monitor to detect problems with this?

https://dashboards.gitlab.net/d/api-rails-controller/api-rails-controller?orgId=1&var-PROMETHEUS_DS=Global&var-environment=gprd&var-stage=main&var-action=GET%20%2Fapi%2Fprojects%2F:id%2Frepository%2Fcommits

Beta groups/projects

If applicable, any groups/projects that are happy to have this feature turned on early. Some organizations may wish to test big changes they are interested in with a small subset of users ahead of time for example.

• gitlab-org/gitlab project
• gitlab-org/gitlab-com groups
• ...

Roll Out Steps

• Enable on staging (/chatops run feature set feature_name true --staging)
• Test on staging
• Ensure that documentation has been updated
• Enable on GitLab.com for individual groups/projects listed above and verify behaviour (/chatops run feature set --project=gitlab-org/gitlab feature_name true)
• Coordinate a time to enable the flag with #production and #g_delivery on slack.
• Announce on the issue an estimated time this will be enabled on GitLab.com
• Enable on GitLab.com by running chatops command in #production (/chatops run feature set feature_name true)
• Cross post chatops Slack command to #support_gitlab-com (more guidance when this is necessary in the dev docs) and in your team channel
• Announce on the issue that the flag has been enabled
• Remove feature flag and add changelog entry
• After the flag removal is deployed, clean up the feature flag by running chatops command in #production channel