fix quiz regrading to not change question names

Test Plan:
  - Before checking out this commit, take a quiz as a student.
  - Check out this commit and go to the quiz show page where you can see
    quiz results.
  - You should see "Question 1" instead of the question title for the
    question as the student.
  - As the teacher, you should see the question title instead of
    "Question 1" when editing the quiz.
  - Question names should show up as "Question 1" etc when previewing
    the quiz as the teacher.

fixes CNVS-11547

Change-Id: I57937c9943cabc7ba27a97ed828df6d410a38ba1
Reviewed-on: https://gerrit.instructure.com/32774
QA-Review: Myller de Araujo <myller@instructure.com>
Reviewed-by: Derek DeVries <ddevries@instructure.com>
Tested-by: Jenkins <jenkins@instructure.com>
Product-Review: Stanley Stuart <stanley@instructure.com>