browser_ui/4_verify/cancelling_merge_request_in_merge_train_spec.rb | Verify Cancelling merge request in merge train when user cancels the merge request does not create a TODO task

This is E2E scenarios for no new To-Do item when a MR in a Merge Train is canceled by a user.

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1. Log into GitLab as premium user
2. Create new group, project and setup runner
3. Enable Merge Train
4. Add CI file to project (make sure there is a little allow enough time for user to cancel MR)
5. Create a MR via API
6. Start merge train
7. User cancel MR
8. Go to To-Dos page
9. Verify no new item with content like Removed from Merge Train <MR ID> "[MR TITLE]" at [NAME SPACE] · [TIME AGO]