reworded sentence to address comma splice and typo

Change-Id: I6e1593e74c47ce681951af8bf2631e2ee08ad439
Reviewed-on: https://gerrit.instructure.com/41218
Reviewed-by: Ryan Florence <ryanf@instructure.com>
Product-Review: Ryan Florence <ryanf@instructure.com>
QA-Review: Ryan Florence <ryanf@instructure.com>
Tested-by: Jenkins <jenkins@instructure.com>