Add sample for fetching total_rows from query results. (#7217)
Add sample for fetching total_rows from query results. (#7217)

* Add sample for fetching total_rows from query results.

* Copypasta

GoogleCloudPlatform/gcloud-python,tswast/google-cloud-python,googleapis/google-cloud-python,tseaver/google-cloud-python,GoogleCloudPlatform/gcloud-python,googleapis/google-cloud-python,tswast/google-cloud-python,tswast/google-cloud-python,tseaver/google-cloud-python,tseaver/google-cloud-python