enable canvas auth on default account during db:initial_setup
enable canvas auth on default account during db:initial_setup

fixes CNVS-24272

test plan:
- run db:initial_setup on a fresh database
- create a user
- after registering the user and logging out, they should be able to log
  back in.

Change-Id: Ib3c837dd0b31c91bdeaa43b1ad425ceae950003c
Reviewed-on: https://gerrit.instructure.com/66818
Reviewed-by: Cody Cutrer <c4fe2b1d90ef8f2548c8aeabfa633434316f0305@instructure.com>
Tested-by: Jenkins
QA-Review: August Thornton <9adc7a1161ddf32ff608de792a7e50179545f026@instructure.com>
Product-Review: Simon Williams <088e16a1019277b15d58faf0541e11910eb756f6@instructure.com>

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