GORM Automigration created a separate `job_storage_infos` table (because
we used it wrong, to be fair), which is actually only used as an
embedded struct in the `jobs` table. This means this table itself can be
dropped.
Replace GORM's auto-migration with Goose. The latter uses hand-written
SQL queries to apply database schema changes, which is safer and easier to
understand than what GORM is doing.
