A mutation to update an existing Milestone on a specific Roadmap based on milestoneID.
A Milestone can only have a single date. It cannot include dates ranges (Start and End Dates) or a bucket time.
Note that the updateMilestone call will only modify fields which are explicitly specified in the call’s arguments. Fields not specified in the arguments in the API call will retain their existing values.
// Update milestone mutation
// Update milestone mutation successful result