Merge branch 'zl/479461' into 'master'

Add column workspaces_agent_config_version and backfill

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/165912



Merged-by: Adam Hegyi <ahegyi@gitlab.com>
Approved-by: Chad Woolley <cwoolley@gitlab.com>
Approved-by: Adam Hegyi <ahegyi@gitlab.com>
Reviewed-by: Chad Woolley <cwoolley@gitlab.com>
Reviewed-by: Terri Chu <tchu@gitlab.com>
Co-authored-by: Zhaochen Li <zli@gitlab.com>