Support incremental database backup on upgrade

Description

As GitLab instances grow each upgrade that includes a database background grows slower and slower. This can be improved by running incremental database backups.

Proposal

Support incremental database backups out of the box.

Links / references

Related to overall incremental baackup: https://gitlab.com/gitlab-org/gitlab-ce/issues/36975

Documentation blurb

Overview

Incremental database backups allow you to save all database changes since your last database backup.

Use cases

Quickly backup database before upgrade.

Feature checklist

Make sure these are completed before closing the issue, with a link to the relevant commit.