CQS: correct-answer ratio donut chart a11y

Closes CNVS-15302

Enhancements:

  - the redundant "Correct answer" is no longer read by SR
  - the chart is ignored by the SR
  - the description is read by the SR: "XX% of your students correctly
    answered this question."

Enhancements to other parts:

  - question description is now read right after the question position
  - no longer using <aside /> for the control button container, so SR
    won't stop to say "Entering (exiting) complimentary landmark", it
    will just speak the button directly instead

TEST PLAN
---- ----

  - go to CQS
  - head over to a question that has the correct-answer donut chart
  - verify the enhancements written above are in effect

Change-Id: Ia689441901bd4d310c3b18c0aafb40f5333246aa
Reviewed-on: https://gerrit.instructure.com/41330
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Ryan Taylor <rtaylor@instructure.com>
Reviewed-by: Derek DeVries <ddevries@instructure.com>
QA-Review: Trevor deHaan <tdehaan@instructure.com>
Product-Review: Derek DeVries <ddevries@instructure.com>