Optimize fetching issues closed by a merge request
cc @dblessing (since you originally wrote the Jira tests)
Related issue: https://gitlab.com/gitlab-org/gitlab-ce/issues/12419
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
cc @dblessing (since you originally wrote the Jira tests)
Related issue: https://gitlab.com/gitlab-org/gitlab-ce/issues/12419