add aXe testing to rubric views
add aXe testing to rubric views

test plan:
- run the spec files edited in this patch normally with
  yarn run jspec-watch path/to/spec
- tests should all pass as expected
- run the spec files edited in this patch with the new command
  yarn run a11y-report path/to/spec
- you should get aXe errors on existing a11y violations

Change-Id: I7061fe2cc631e04bfb3c2469bb2bc8b2791ba62c
Reviewed-on: https://gerrit.instructure.com/131007
Tested-by: Jenkins
Reviewed-by: Steven Burnett <a0b450117c5d20a22d5c4d52bb8ae13adee003d8@instructure.com>
Product-Review: Matt Berns <e53c8988cd428dde240324ce2797c8eb7073560f@instructure.com>
QA-Review: Matt Berns <e53c8988cd428dde240324ce2797c8eb7073560f@instructure.com>

djbender/canvas-lms,djbender/canvas-lms,instructure/canvas-lms,djbender/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,djbender/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,instructure/canvas-lms