test(db): the legacy step map knows the tour type migration

Migration20200101042300_every_tour_type_the_contract_names runs after
the legacy steps like the other post-legacy migrations, but was missing
from the test's list of migrations without a step, so LEGACYMAP-001
failed.

server/tests/unit/db/legacy-baseline.test.ts

@@ -34,6 +34,7 @@ const UNNUMBERED = [
   'Migration20200101042000_tours',
   'Migration20200101042100_a_trip_reminder_remembers_it_was_sent',
   'Migration20200101042200_an_index_on_every_foreign_key',
+  'Migration20200101042300_every_tour_type_the_contract_names',
 ];
 // The last step the positional runner ever had; planLegacyBaseline refuses a
 // schema_version past it.