Add parquet format to load job configuration docs (#1035)
Add parquet format to load job configuration docs (#1035)


googleapis/google-cloud-php,googleapis/google-cloud-php,googleapis/google-cloud-php,chingor13/google-cloud-php,chingor13/google-cloud-php,jdpedrie/google-cloud-php,jdpedrie/google-cloud-php,chingor13/google-cloud-php,jdpedrie/google-cloud-php