spec: fix general_api_spec for rails 3

Change-Id: Ibf4fe359a92305957f9d44204c248677a8d23b3c
Reviewed-on: https://gerrit.instructure.com/30803
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Cody Cutrer <cody@instructure.com>
Product-Review: James Williams  <jamesw@instructure.com>
QA-Review: James Williams  <jamesw@instructure.com>