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Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Depends on https://gitlab.com/gitlab-org/gitlab_git/merge_requests/17 being merged, a new gitlab_git being released and this MR's Gemfile.lock being updated..
See private issue https://dev.gitlab.org/gitlab/gitlabhq/issues/2173.
To do after this is merged: Update https://gitlab.com/gitlab-org/omnibus-gitlab/blob/master/files/gitlab-cookbooks/gitlab/templates/default/sv-sidekiq-run.erb in omnibus.