fix autocomplete on merge-users page
fix autocomplete on merge-users page

fixes ADMIN-1366

test plan:
 - Go to Admin->People->Merge with another user
 - Type in the name box, ensure it returns options from autocomplete
 - Selecting a user goes to confirmation page

Change-Id: Ifb097c62bafd6cb9bb1297b256f5e8e9ead1c623
Reviewed-on: https://gerrit.instructure.com/161637
Tested-by: Jenkins
Reviewed-by: James Williams  <3a5f4ed991dbfa5c9ef76ad729d240ca12f62180@instructure.com>
QA-Review: Anju Reddy <851202533fb1f0b615e4547ba226c76996d060dd@instructure.com>
Product-Review: Carl Kibler <7c2b40129dd885a147d5b2dda56dda016b9a8f57@instructure.com>

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