Add require_partition_filter in bigquery.external_config.HivePartitioningOptions #255

I want to force partition filters when user run queries on external tables that uses HivePartitioning.

Please add property require_partition_filter within bigquery.external_config.HivePartitioningOptions()

I tried using table.require_partition_filter = True, but I get an error when my table contains hive_partitioning within external_data_configuration:

google.api_core.exceptions.BadRequest: 400 POST require_partition_filter has been set for a hive-partitioned table without using the HivePartitioningOptions. To configure external, hive-partitioned tables -- including setting require_partition_filter -- please use the HivePartitioningOptions. Setting require_partition_filter on the top-level table definition, or via the TimePartitioning field, does not configure hive-partitioned tables.