Creates the two tables Managoat.OAuth needs, from a migration of the host's own (the shape Oban uses; a hex package cannot run mix ecto.migrate for its host). In MyApp.Repo.Migrations.AddOAuth, say:

use Ecto.Migration

def up, do: Managoat.OAuth.Migration.up()
def down, do: Managoat.OAuth.Migration.down()

Options, the same for up/1 and down/1:

• :subject_column — the name of the column that holds the host's subject, :user_id by default. It is a binary_id with no foreign key; a host that wants one references its own table in the same migration (alter table(:oauth_authorization_codes) do modify ...).
• :prefix — the Postgres schema to create the tables in, the default schema when nil. Pass the same value as prefix: in the instance's config. up/1 creates the schema first unless create_schema: false.