spec: Verify preview urls for locked/hidden files
spec: Verify preview urls for locked/hidden files

refs MAT-560
flag= none

test plan:
-passes jenkins

Change-Id: Ie1b1c78fca50cb73431569a376ade4997b84c50f
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/286874
Tested-by: Service Cloud Jenkins <9144042a601061f88f1e1d7a1753ea3e2972119d@instructure.com>
Reviewed-by: Weston Dransfield <e9203059795dc94e28a8831c65eb7869e818825e@instructure.com>
QA-Review: Weston Dransfield <e9203059795dc94e28a8831c65eb7869e818825e@instructure.com>
Product-Review: Jacob DeWar <185eb844d707bf97b714ed89a7539a3325c4b423@instructure.com>

sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms