0ca94af397
Follow the same pattern of the other jobs which deploy devstack but runs also functional tests (see devtack-tox-functional and devstack-tox-functional-consumer). Without this, the older branches where cinderlib functional tests use Python 2 (stein, and soon train when that is branched) fails because they try to install packages part of which are Python 3 only. Change-Id: Ibd2862f30d4c451118fb96d1f56a09fd66b2d75a