[Java BQ] Default null array in Beam Row to empty array

[ahmedabu98]

We should relax our type checking and default null array values to empty arrays. This is already done for TableRows [1] and is also the behavior of GoogleSQL [2]

[1]

beam/sdks/java/io/google-cloud-platform/src/main/java/org/apache/beam/sdk/io/gcp/bigquery/TableRowToStorageApiProto.java

Lines 845 to 849 in 111f4c3

	if (bqValue == null) {
	if (fieldDescriptor.isOptional() || allowMissingRequiredFields) {
	return null;
	} else if (fieldDescriptor.isRepeated()) {
	return Collections.emptyList();

[2] https://cloud.google.com/bigquery/docs/reference/standard-sql/data-types#array_type