Update BigQueryIO Documentation (#28591)

* Update BigQueryIO Documentation

- Updated the description regarding failed rows for Storage Write API.
- Made `PCollection` formatting consistent.

* Update website/www/site/content/en/documentation/io/built-in/google-bigquery.md

website/www/site/content/en/documentation/io/built-in/google-bigquery.md

@@ -883,10 +883,9 @@ explicitly enable this using [`withAutoSharding`](https://beam.apache.org/releas
 ***Note:*** Auto sharding with `STORAGE_WRITE_API` is supported on Dataflow's legacy runner, but **not** on Runner V2
 {{< /paragraph >}}
 
-When using `STORAGE_WRITE_API`, the PCollection returned by
-[`WriteResult.getFailedInserts`](https://beam.apache.org/releases/javadoc/current/org/apache/beam/sdk/io/gcp/bigquery/WriteResult.html#getFailedInserts--)
-will not contain the failed rows. If there are data validation errors, the
-transform will throw a `RuntimeException`.
+When using `STORAGE_WRITE_API`, the `PCollection` returned by
+[`WriteResult.getFailedStorageApiInserts`](https://beam.apache.org/releases/javadoc/current/org/apache/beam/sdk/io/gcp/bigquery/WriteResult.html#getFailedStorageApiInserts--)
+will contain the rows that failed to be written to the Storage Write API sink.
 
 #### At-least-once semantics
 
@@ -901,10 +900,9 @@ specify the number of streams, and you can’t specify the triggering frequency.
 
 Auto sharding is not applicable for `STORAGE_API_AT_LEAST_ONCE`.
 
-When using `STORAGE_API_AT_LEAST_ONCE`, the PCollection returned by
-[`WriteResult.getFailedInserts`](https://beam.apache.org/releases/javadoc/current/org/apache/beam/sdk/io/gcp/bigquery/WriteResult.html#getFailedInserts--)
-will not contain the failed rows. If there are data validation errors, the
-transform will throw a `RuntimeException`.
+When using `STORAGE_API_AT_LEAST_ONCE`, the `PCollection` returned by
+[`WriteResult.getFailedStorageApiInserts`](https://beam.apache.org/releases/javadoc/current/org/apache/beam/sdk/io/gcp/bigquery/WriteResult.html#getFailedStorageApiInserts--)
+will contain the rows that failed to be written to the Storage Write API sink.
 
 #### Quotas