Fix Rubocop CyclomaticComplexity offense
This backport a change pushed to the Upstream merge branch (https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/1725).
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
This backport a change pushed to the Upstream merge branch (https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/1725).