Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
It reverts https://dev.gitlab.org/gitlab/gitlabhq/commit/40e31e1db31e6ba9a1cd6255afc2f09df61f4060
and fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/2048 and https://gitlab.com/gitlab-org/gitlab-ce/issues/2043