Track historical milestone assignments on an issue and also burndown charts
Per https://gitlab.com/gitlab-org/gitlab-ce/issues/52850#note_110422657, we want some way to track issues that have changing milestones. Should we track historical changed milestones somehow? How would GitLab use that to help with tracking?
Also, burndown charts should be updated to capture work being moved from one sprint to another sprint and the impact of it.
Edited by Victor Wu