Revisit Architectural Design Document for Approval Rules Re-architecture
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Iterate and refine on https://gitlab.com/gitlab-org/gitlab/-/issues/498454+ now that we have more information available to incorporate.
## What should we include in the document?
- Revisit models, tables and relationships.
- Include benchmarks, specifically the number of queries we were sending to the DB during the sync.
- Create a plan to benchmark all the DB transactions related.
- Consider this [follow-up issue](gitlab-com/content-sites/handbook#420) as part of the refinement process.
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