Sprint report shows wrong issue status if the column isn't mapped in the board

Steps to reproduce

1. Create a board that uses a filter which contain at least one issue
2. In the board "Column mapping", do not map the "Closed" status to any column
3. Create a sprint with at least one issue in it
4. Transition one of these issues to the "Closed" status
5. Close the sprint
6. Open the sprint report

Current behaviour

The issue will appear in a different status in the sprint report.

Expected behaviour

Show the issue in the correct status even though the status isn't mapped.

Workaround

Map the status to any column in the board configuration