HAWQ-791. Fix test issue in parquet test.
HAWQ-791. Fix test issue in parquet test.

huor/incubator-hawq,huor/incubator-hawq,lavjain/incubator-hawq,wengyanqing/incubator-hawq,wengyanqing/incubator-hawq,wengyanqing/incubator-hawq,lavjain/incubator-hawq,huor/incubator-hawq,stanlyxiang/incubator-hawq,stanlyxiang/incubator-hawq,jianlirong/incubator-hawq,stanlyxiang/incubator-hawq,lavjain/incubator-hawq,outofmem0ry/incubator-hawq,stanlyxiang/incubator-hawq,lavjain/incubator-hawq,jianlirong/incubator-hawq,lavjain/incubator-hawq,outofmem0ry/incubator-hawq,stanlyxiang/incubator-hawq,lavjain/incubator-hawq,wengyanqing/incubator-hawq,outofmem0ry/incubator-hawq,wengyanqing/incubator-hawq,huor/incubator-hawq,wengyanqing/incubator-hawq,jianlirong/incubator-hawq,lavjain/incubator-hawq,outofmem0ry/incubator-hawq,outofmem0ry/incubator-hawq,outofmem0ry/incubator-hawq,huor/incubator-hawq,stanlyxiang/incubator-hawq,outofmem0ry/incubator-hawq,wengyanqing/incubator-hawq,outofmem0ry/incubator-hawq,wengyanqing/incubator-hawq,jianlirong/incubator-hawq,huor/incubator-hawq,jianlirong/incubator-hawq,jianlirong/incubator-hawq,lavjain/incubator-hawq,stanlyxiang/incubator-hawq,jianlirong/incubator-hawq,huor/incubator-hawq,jianlirong/incubator-hawq