Function migrate_data_dir_to 

pub async fn migrate_data_dir_to(
    source_dir: &Path,
    destination_dir: &Path,
    destination_engine: StorageEngine,
) -> Result<StoreMigrationReceipt, PortError>

migrate_data_dir with the destination engine chosen. Kept for API compatibility; current binaries only contain SQLite and cannot read format-1 stores.