don't hide the form submit buttons along with "Delete My Account"

test plan:
 - an admin user should see the "Delete My Account" link
   in /profile/settings, after clicking Edit
 - a non-admin user with a SIS ID should not see that link,
   but should still see the "Cancel" and "Update Settings"
   buttons

fixes CNVS-15429

Change-Id: I338e3027c9caefa6978738c73dd2c6aa2b75775e
Reviewed-on: https://gerrit.instructure.com/40921
Product-Review: Cosme Salazar <cosme@instructure.com>
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Ryan Shaw <ryan@instructure.com>
QA-Review: Clare Strong <clare@instructure.com>