feat: Add gitlab_sec DB support

What

Adds support for gitlab_sec DB, depending on https://gitlab.com/gitlab-com/gl-infra/ansible-workloads/database-lab-scripts/-/merge_requests/17.

Note I'm super unfamiliar with this project so I essentially copied every reference I could find to ci but would appreciate someone's expert eyes.

Relates to Add gitlab_sec to testing bot (#158 - closed) and gitlab-com/gl-infra/data-access/dbo/dbo-issue-tracker#378