update pysqlflow to use 0.7.0 (#1034)
update pysqlflow to use 0.7.0 (#1034)

* update pysqlflow to use 0.7.0

* add apt-get update in build_docker_image.sh

sql-machine-learning/sqlflow,sql-machine-learning/sqlflow,sql-machine-learning/sqlflow,sql-machine-learning/sqlflow,sql-machine-learning/sqlflow,sql-machine-learning/sqlflow