test plan:
- when starting a blueprint migration via the API, you should be
able to add a comment via the `comment` parameter
- when listing blueprint migrations, the comment should be
included
closes MC-167
Change-Id: Ib91dc8917f736c217b2cc02d253c344fb1c14c3e
Reviewed-on: https://gerrit.instructure.com/109666
Tested-by: Jenkins
Reviewed-by: James Williams <jamesw@instructure.com>
QA-Review: Heath Hales <hhales@instructure.com>
Product-Review: Jeremy Stanley <jeremy@instructure.com>