Possibility to close the Sprint when there are unmapped statuses (such as Cancelled)

Problem Definition

Currently, JIRA will only consider issues in Sprints as completed if its status is mapped to the very last column on the board.

The customer would like to see the issues with status Cancelled on the board and would like to be able to close the Sprint without the warning message that these issues are not completed.

Suggested Solution

Add possibility to have some statuses (such as Cancelled), to not be shown on the board and be able to complete the Sprint.