Issue Summary

Custom status category can't be changed in team-managed project workflow.

Steps to Reproduce

1. Create a team-managed Software development Scrum project.
2. Create a few issues 
3. Open the Task work items
4. Click Configure (fields)
5. Click Edit Workflow in new editor
6. Add a new workflow status Schedule (to do category)
7. Click Update Workflow
8. Select all the default issue types and save changes
9. Allign the new Status on the Board
10. In the Workflow editor , Click Schedule and try to change its Category to "in progress" and click "update"

Expected Results

The Schedule category is changed to in progress and editor becomes dirt to update the worflow. 

Actual Results

The Schedule category remains to do

...

Workaround

Delete the status you want to edit and create a new one with new category and when you update the workflow wizard will ask to move the issues to a new status. You can select the new status with desired category you created.