Add migration uuid API schema validation for 2.59

Microversion 2.59 [1] compute API added a "uuid" parameter to the body of
the following migration responses:

- GET /os-migrations
- GET /servers/{server_id}/migrations/{migration_id}
- GET /servers/{server_id}/migrations

This commit adds the uuid to the response validation schema for
list_migrations.

[1] https://docs.openstack.org/nova/latest/reference/api-microversion-history.html#id55

Change-Id: Ic748f70d90446c79324df30147e4a270b72d710e
4 files changed