Use severity warn, not severity low
cc @bjk-gitlab
Cross reference: https://gitlab.com/gitlab-cookbooks/gitlab-prometheus/merge_requests/321
Edited by Andrew Newdigate
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
cc @bjk-gitlab
Cross reference: https://gitlab.com/gitlab-cookbooks/gitlab-prometheus/merge_requests/321