This PR will be tagged bigquery/v1.8.0

Change-Id: I3ff32202395a9cad099f4acfd272f7abd39d937a
Reviewed-on: https://code-review.googlesource.com/c/gocloud/+/56612
Reviewed-by: kokoro <[email protected]>
Reviewed-by: Cody Oss <[email protected]>