Omit year from epic start date in collapsed sidebar if the same as finish date
In an epic, if the start and finish dates are in the same year, omit the year from the start date in the collapsed sidebar. Example:
- Start date: Oct 18 2017
- Finish date: Oct 31 2017
Originally from: https://gitlab.com/gitlab-org/gitlab-ee/issues/3556#note_45690263