spec: Skip the CDC schema check that runs on migrations
spec: Skip the CDC schema check that runs on migrations

It's failing on some issue unrelated to the migrations in
the given commit.

Change-Id: I1aef9172e8cc767805c3bc9e55cc96787630833d
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/254208
Tested-by: Service Cloud Jenkins <9144042a601061f88f1e1d7a1753ea3e2972119d@instructure.com>
Reviewed-by: Wagner Goncalves <1386d52ba3130eb1a5647e5b47f1073537d5ef43@instructure.com>
QA-Review: Tucker Mcknight <4b51b98c1d84aa97854d216bd061ce5d3eda8a28@instructure.com>
Product-Review: Tucker Mcknight <4b51b98c1d84aa97854d216bd061ce5d3eda8a28@instructure.com>

sfu/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,instructure/canvas-lms