[serdes] move most of the models over to using spec (#46966)

...ackend/test/metabase_enterprise/models/entity_id_test.clj

...est/metabase_enterprise/serialization/v2/extract_test.clj

...d/test/metabase_enterprise/serialization/v2/load_test.clj

...test/metabase_enterprise/serialization/v2/models_test.clj

...est/metabase_enterprise/serialization/v2/storage_test.clj

src/metabase/models/card.clj

src/metabase/models/dashboard.clj

src/metabase/models/database.clj

src/metabase/models/field_values.clj

src/metabase/models/native_query_snippet.clj

src/metabase/models/pulse.clj

src/metabase/models/pulse_card.clj

src/metabase/models/pulse_channel.clj

src/metabase/models/segment.clj

src/metabase/models/serialization.clj

src/metabase/models/table.clj

src/metabase/models/timeline.clj

src/metabase/models/timeline_event.clj

test/metabase/models/pulse_card_test.clj

test/metabase/models/pulse_channel_test.clj