* and stop setting default values in python operator code, so defaults can be set at the server side.

This issue is just for the PR and questions from maintainers. 
tests/providers/yandex/operators/test_yandexcloud_dataproc.py
operator = DataprocCreateClusterOperator(
            task_id='create_cluster',
            ssh_public_keys=SSH_PUBLIC_KEYS,
            folder_id=FOLDER_ID,
            subnet_id=SUBNET_ID,
            zone=AVAILABILITY_ZONE_ID,
            connection_id=CONNECTION_ID,
            s3_bucket=S3_BUCKET_NAME_FOR_LOGS,
            cluster_image_version=CLUSTER_IMAGE_VERSION,
        )
        context = {'task_instance': MagicMock()}
        operator.execute(context)
        create_cluster_mock.assert_called_once_with(
            cluster_description='',
            cluster_image_version='1.1',
            cluster_name=None,
            computenode_count=0,
            computenode_disk_size=15,