When testing, use the schema we use in development, staging and production environments

Right now we are using a slightly different schema since we are not migrating the schema on tests using the migrations we've written. We usually let Gorm do that with its "Automigrate" feature, but that ends up creating a very-similar-but-not-the-same database schema.

In order to make tests actually test the features against the schema we've designed, the way tests migrate the database should be changed.