On timed quizzes, enhance warning for users with unfinished questions who click Finish Exam

[sschaub]

Is your feature request related to a problem? Please describe. On a timed quiz, when a user clicks Finish Exam and has skipped questions, there is no warning that questions have been skipped.

Describe the solution you'd like When the user clicks Finish Exam, if the user has skipped questions, display a second dialog indicating which questions have been skipped. For example: "You have not answered the following questions: 2, 5, 7. Are you sure you wish to submit?".

[github-actions[bot]]

Stale issue message

[bnmnetp]

See also #1159 as another way to make sure students complete all of their questions.

[bnmnetp]

This is very difficult to do anymore as the browsers do not let us show custom dialog boxes when a user is trying to leave the page. So perhaps a different approach such as showing the number of unanswered questions very prominently on the timed exam page would provide similar guidance to a user.