[JIRAALIGN-1075] Jira Align Admin > Jira Management > Jira Boards mapping error for 'Multiple Jira Sprints mapped to a Jira Align Sprint' when the errant sprints are removed from board

Issue Summary:
Jira Align Admin > Jira Management > Jira Boards mapping error for 'Multiple Jira Sprints mapped to a Jira Align Sprint' when the errant sprints are removed from board

Steps to Reproduce:
1. Navigate to Jira Align Admin > Jira Management > Jira Boards and view a board where their are two or more jira sprints with the same recommended Jira Align sprint and all but one of the sprints is removed from the board

Actual Results:
Error for 'Multiple Jira Sprints mapped to a Jira Align Sprint' shows when all but one of the multiple Jira sprints pointing to the same Jira Align sprint are removed

Expected Results:
Error for 'Multiple Jira Sprints mapped to a Jira Align Sprint' would not show when all but one of the multiple Jira sprints pointing to the same Jira Align sprint are removed

Workaround:
This error is strictly visual and can be ignored until the fix is made if all but one of the duplicate sprints has been removed from the board.