viewing student progressions requires "view all grades"

test plan: confirm that, with draft state off and on, only
users whose role grants "view all grades" can view module progressions
for students other than the user (or the user's observees).

fixes CNVS-12262

Change-Id: Ie92ae43bc11bd0479d8172d93e5df47d006305a7
Reviewed-on: https://gerrit.instructure.com/33763
Reviewed-by: James Williams  <jamesw@instructure.com>
QA-Review: Clare Strong <clare@instructure.com>
Tested-by: Jenkins <jenkins@instructure.com>
Product-Review: Hilary Scharton <hilary@instructure.com>