Parallelize GCS and BQ connectors Maven integration tests.
Parallelize GCS and BQ connectors Maven integration tests.

Reduces GCS and BQ connectors release time.

	Change on 2018/06/15 by idv <idv@google.com>

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=200720914

GoogleCloudDataproc/hadoop-connectors,GoogleCloudDataproc/hadoop-connectors