Later migrations added fields to the EE DB which were used by factories which were used in these specs.
And in CE on MySQL, a single appearance row is enforced.
The migration and migration specs should not depend on the codebase staying the same.
* Hopefully fixes spec failures in which the table doesn’t exist
* Decouples the background migration from the post-deploy migration, e.g. we could easily run it again even though the table is dropped when finished.