Workarounding the upstream ansible apt module bug
documented here:
https://github.com/ansible/ansible-modules-core/pull/1517
For the next versions of ansible we'll be using, we should
check if the apt bug is fixed. When it's fixed, we could
abandon this change and use the standard apt module
with correct cache handling.
Change-Id: I2aaf00da175f31d0157bbc4ae30a4e176b055078