User Double Clicking the Take Quiz Button Causes the Quiz to Complete With All Questions Skipped

This is a really odd bug that we ran into where if a user that is trying to take a quiz accidentally double clicks on the Take tab for the quiz it will automatically finish the quiz giving them a result with all questions skipped. This is particularly problematic in a school setting where quizzes can only be taken a single time.

I have attached a patch that fixes this issue by updating a line of code in _quiz_resume_existing_quiz to match all of the similar locations where this value is setup.