The venv module is part of the default Python installations in most
Linux distributions except the Debian line. However, we had this already
installed on Debian images, but not on Ubuntu images. This is required
for Qt Interface Framework.
Change-Id: I255f27edf53acbb7ab258d5495636759bddc888b
Reviewed-by: Heikki Halmet <heikki.halmet@qt.io>
Reviewed-by: Tero Heikkinen <tero.heikkinen@qt.io>