Make `bug`, `feature`, and `backstage` issue type labels to be scoped labels

Part of https://gitlab.com/gitlab-org/gitlab-ce/issues/60166.

The idea is to migrate:

1. ~bug to ~"type::bug"
2. feature to ~"type::feature"
3. tooling to ~"type::tooling"
4. security to ~"type::security"
5. documentation to ~"type::documentation"

TODO:

1. Prepare a MR for https://gitlab.com/gitlab-org/gitlab-ce: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/29563
2. Prepare a MR for https://gitlab.com/gitlab-org/quality/triage-ops: gitlab-org/quality/triage-ops!150 (closed)
3. Prepare a MR for https://gitlab.com/gitlab-org/gitlab-insights: gitlab-insights!114 (closed)
4. Prepare a MR for https://gitlab.com/DylanGriffith/knative-bots/blob/master/lib/throughput_labels.rb
5. Prepare a MR for https://gitlab.com/gitlab-com/www-gitlab-com: gitlab-com/www-gitlab-com!24219 (closed)
6. Change the group labels
7. Announce it on Slack and team call