rails3: fix account_admin_question_bank_content specs

Change-Id: I96ecf15ffcd726adcee289fd0bb6ece60e88fb40
Reviewed-on: https://gerrit.instructure.com/31668
Reviewed-by: Cody Cutrer <cody@instructure.com>
Tested-by: Jenkins <jenkins@instructure.com>
Product-Review: Cameron Matheson <cameron@instructure.com>
QA-Review: Cameron Matheson <cameron@instructure.com>