[JIRAALIGN-1217] Closing a Sprint in Jira and moving stories to Unassigned Backlog does not Change the Jira Align Story's sprint to Unassigned Backlog

Issue Summary

Whenever a sprint is closed in Jira and any incomplete stories are moved to the Jira Backlog, the corresponding Jira Align issues are not moved to the "Unassigned Backlog" in Jira align. Instead, the last completed sprint is listed in the Jira Align Story's "Sprint" field. This causes a discrepancy in the count between the number of stories in the unassigned backlog in Jira and the unassinged backlog on Jira Align.

Steps to Reproduce

1. In Jira, close an active Sprint with uncompleted stories in it.
2. While still in Jira, move any of the left over, incomplete stories to Jira's Unassigned Backlog.

Expected Results

On Jira Align, the Sprint field in the corresponding story should also move to Unassigned Backlog.

Actual Results

The Jira Align Story retains the last completed sprint that was closed in Jira and is not automatically moved to the Unassigned backlog

Root Cause

• Jira retains the historical sprint data on stories. If a non-completed Story was part of a completed Sprint and is moved to the Jira backlog or to any other sprint, the completed sprint data is retained in the Jira Story's sprint field.
• In other words, even if a story is moved to another sprint, those previous completed sprints are also recorded in the sprint field in addition to the new sprint that the story was moved to.
• Jira Align pulls the story data from the issue via the API and records whatever data is currently in the custom field for the story at the time.
• Jira apparently has no way to flag a story as being in the Jira "backlog" in the sprint field, thus, Jira Align has no way of knowing if a Story is sitting in Jira's backlog and not currently part of a Sprint due to that field being populated.

Workaround

If the user wants the number of Jira Backlog stories to line up with Stories in the Unassigned Backlog on the Jira Align side, then the "sprint" field must be nulled out on the Jira Story. It is not easy to remove the Sprints, per:
https://jira.atlassian.com/browse/JSWSERVER-9786
https://jira.atlassian.com/browse/JSWSERVER-10548
If the historical Sprint data is not relevant to the userr, they can remove any of the old sprints from affected stories via bulk edit in Jira as described in the workaround in:

https://jira.atlassian.com/browse/JSWSERVER-10548

This will set the custom field for the story to 'null', move it to Jira's backlog ( if it wasn't there already) and, in turn, set the Sprint field on the Jira Align story to "Unassigned Backlog" when Jira and Jira Align sync up.