fix creating notification policies on the correct shard

Change-Id: Ib242e47f10e88349dcceb05b187b18abb7af1a0b
Reviewed-on: https://gerrit.instructure.com/29996
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Rob Orton <rob@instructure.com>
Product-Review: Cody Cutrer <cody@instructure.com>
QA-Review: Cody Cutrer <cody@instructure.com>