[Grades Submission] - Show failure message when signing fails
When the users submit a grades' file and their institute requires digital signing, they should see a failure message when signing fails. One would expect, that once digital signing fails the file would be invalidated and they get a failure message. Instead they see the following screen and when they press close, the grades file isn't listed below, and they have no idea that submission failed. Also when they press close, cancelCourseExamDocument
is fired.