[Feature flag] Enable `usage_data_track_ci_templates_unique_projects`

What

Remove the usage_data_track_ci_templates_unique_projects feature flag

Previous issue: #219457 (closed)

Owners

• Team: ~"group::configure"
• Most appropriate slack channel to reach out to: #s_configure
• Best individual to reach out to: @hfyngvason (@Hordur on Slack)

Expectations

What are we expecting to happen?

Redis HLL usage data gets collected for unique project ids of pipelines using the templates listed in #219457 (closed)

What might happen if this goes wrong?

• A high volume of redis HLL event could overload redis (in this case, we turn off this feature flag)
• The extra redis calls (only when the templates are included) could impact CI

What can we monitor to detect problems with this?

• Redis monitoring dasbhoard (internal link)
• Alerts and dashboards in place for CI (internal link)

Beta groups/projects

Roll Out Steps

• Confirm that QA tests pass with the feature flag enabled (if you're unsure how, contact the relevant stable counterpart in the Quality department)
• Enable on staging (/chatops run feature set usage_data_track_ci_templates_unique_projects 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 usage_data_track_ci_templates_unique_projects true)
• Coordinate a time to enable the flag with the SRE oncall and release managers
  • In #production mention @sre-oncall and @release-managers. Once an SRE on call and Release Manager on call confirm, you can proceed with the rollout
• 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 usage_data_track_ci_templates_unique_projects 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

Rollback Steps

• This feature can be disabled by running the following Chatops command:

/chatops run feature set usage_data_track_ci_templates_unique_projects false