Force new_math_handling flag off in question banks
Force new_math_handling flag off in question banks

closes LS-1938
flag=none

since the question bank page is the same as quiz question editing,
this makes sense.

test plan:
  - turn the new_math_equation_handling flag on
  - go to /courses/:id/question_banks
  - open a question bank
  > expect ENV.FEATURES.new_math_equation_handling to be false

Change-Id: I4cd232ed3ce02a992290944877568414ddec48ca
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/259535
Tested-by: Service Cloud Jenkins <9144042a601061f88f1e1d7a1753ea3e2972119d@instructure.com>
Reviewed-by: Jeff Largent <346e902a52b2e977849f8d9756038ae5621be6de@instructure.com>
QA-Review: Jeff Largent <346e902a52b2e977849f8d9756038ae5621be6de@instructure.com>
Product-Review: Ed Schiebel <0ca8a83847a5889cf05cb219c0ab09f6b646243b@instructure.com>

sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms