support hard_deletes `new_record` behavior for snapshots

[benjibuiltit]

As of dbt-core 1.9 snapshot hard_deletes config supports new_record which this adaptor does not support.
https://docs.getdbt.com/reference/resource-configs/hard-deletes

invalidate behavior works just fine, but when running snapshots with new_record, the dbt_is_deleted column is never populated.