is_resumable added and used on UI to allow resume on error exam attempts reviewed
[feat]: MST-817 allow exam attempt to be resumable through the new is_resumable model field. Expose the is_resumable boolean field from the ProctoredExamStudentAttempt table through the proctoring API and restful web API. Update the UI to use the is_resumable property on the attempt model instead of 'error' status. This change will allow exams to be resumable even if the attempt is in reviewed status like 'verified' or 'rejected'