remove redundant and incorrect TAB_PEOPLE check
remove redundant and incorrect TAB_PEOPLE check

this code was added (g/2783) before a proper :read_roster
permission check was put in (g/5092). it's no longer needed.

test plan:
 - an observer with "See the list of users" permission should
   be able to see the People tab on the left side of course nav
   (the actual page was already readable)

fixes CNVS-15980

Change-Id: Ib79c5a0a640009ba33f889386ba62ea7b0bfe105
Reviewed-on: https://gerrit.instructure.com/127016
Tested-by: Jenkins
Reviewed-by: Jon Willesen <0321efbc0acf6204eb6035acb1d418838b450d08@instructure.com>
QA-Review: Deepeeca Soundarrajan <5bcd4b623f00b7fc2942cd1c65c245b30a48a61f@instructure.com>
Product-Review: Jeremy Stanley <b3f594e10a9edcf5413cf1190121d45078c62290@instructure.com>

sfu/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,djbender/canvas-lms,venturehive/canvas-lms,djbender/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,venturehive/canvas-lms,venturehive/canvas-lms,sfu/canvas-lms,djbender/canvas-lms,sfu/canvas-lms,venturehive/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,djbender/canvas-lms