tests: increase timeout to 5 seconds in setBucketPolicy tests (#657)
tests: increase timeout to 5 seconds in setBucketPolicy tests (#657)

Mint shows failures for setBucketPolicy() tests even after 3 seconds
timeout against minio gateway where backend is Amazon AWS S3. This
patch increases timeout to 5 seconds.
minio/minio-java,balamurugana/minio-java,vadmeste/minio-java