Merge branch '440185-optimize-merge-diff-query' into 'master'

Optimizing merge_request search using latest_mr_diff_id

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/169979



Merged-by: Max Fan <mfan@gitlab.com>
Approved-by: Alex Buijs <abuijs@gitlab.com>
Approved-by: Eugie Limpin <elimpin@gitlab.com>
Approved-by: Marius Bobin <mbobin@gitlab.com>
Reviewed-by: Marius Bobin <mbobin@gitlab.com>
Reviewed-by: Pedro Pombeiro <noreply@pedro.pombei.ro>
Reviewed-by: Max Fan <mfan@gitlab.com>