This mirrors a nearly identical change made to apt_repository.py.
Also removes the use of apt-get --force-yes as it can be dangerous
and should not be necessary (apt_repository.py does not use it).
Repeating the explanation from the apt_respository change below:
Since use_unsafe_shell is suspicious from a security point
of view (or it wouldn't be unsafe), the less we have, the less
code we have to thoroughly inspect for a security audit.
In this case, the '&&' can be replaced by doing 2 calls to run_command.
e56d668ade