Story Point value reset to zero/removed is ignored on Burnup Chart

Issue Summary

Story Point value reset to zero/removed is ignored in Burnup Chart Work scope.

Steps to Reproduce

Scenario 1

1. Create a sprint with a few issues
2. Add Estimates to issues
3. Start the sprint
4. Now, increase/decrease the estimate points to any issues and the same will reflect in the Burnup chart
5. For any issue in a sprint, try to reset the estimated value to zero or remove the estimated value then, Burnup chart ignores to update work scope details.
   
   Burnup chart should show the value as reduced from 15–>10 but, when zero/remove estimated value Burnup chart ignores to update work space details.
   

Scenario 2

1. Create a new Story issue (TEST-1) and assign 3 story points.
2. Create a second Story issue (TEST-2) and assign 3 story points.
3. Remove all the story points from TEST-1 (story points estimation should be null or empty).
4. Move TEST-2 to a new sprint and start the sprint.
5. Assign TEST-1 to the active sprint.
6. Move TEST-1 and TEST-2 to DONE status.
7. Closed the active sprints.
8. In the burnup chart, we can see TEST-1 completed works were calculated as 3 and included in the completed work and work scope:
   

Expected Results

Burnup chart should show the Work scope value changing to '0'.

Actual Results

Burnup chart ignores when we reset the estimated value to Zero/removed.

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available