Merge branch '427337-unified-backups-metadata' into 'master'

Unified Backups: Introduce `backup_information.json` metadata

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/149441



Merged-by: Michael Kozono <mkozono@gitlab.com>
Approved-by: Michael Kozono <mkozono@gitlab.com>
Reviewed-by: Michael Kozono <mkozono@gitlab.com>
Co-authored-by: Gabriel Mazetto <gabriel@gitlab.com>