spec: bullet test.rb require tweak

Change-Id: Ibe9e0d709e997b6c010c98adfe9e8a4c68bdd7b0
Reviewed-on: https://gerrit.instructure.com/30137
Reviewed-by: Shawn Meredith <shawn@instructure.com>
Product-Review: Shawn Meredith <shawn@instructure.com>
QA-Review: Shawn Meredith <shawn@instructure.com>
Tested-by: Shawn Meredith <shawn@instructure.com>