Merge branch 'vulnerability-management-policy/save-policy' into 'master'

Allow to save and update vulnerability management policy

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/158255



Merged-by: Alexander Turinske <aturinske@gitlab.com>
Approved-by: Alexander Turinske <aturinske@gitlab.com>
Reviewed-by: Alexander Turinske <aturinske@gitlab.com>
Co-authored-by: lorenzvanherwaarden <lvanherwaarden@gitlab.com>