Disable the `unattended-upgrades` service

`unattended-upgrades` sometimes do not complete in time and other parts
of the setup that use `apt` fail with a variation of:

    E: Could not get lock /var/lib/dpkg/lock-frontend. It is held by process 7929 (unattended-upgr)

Change-Id: I45cd044dd99a94ec4749db97afa18c71847a8ce1
2 files changed