Revert "Revert "Install.py: Prevent prompts from breaking apt""
Revert "Revert "Install.py: Prevent prompts from breaking apt""

This reverts commit 67a616a97927efdc4fbcc5edb0d0cf4a724d90e2.

Sigh.  As it turns out, /etc/default/grub being hacked also
causes the same problem.  I think there's a way to fix that cleanly
as well, but until then, replacing the "accept installed version"
hack here so jobs can run.

tchaikov/teuthology,yghannam/teuthology,ceph/teuthology,zhouyuan/teuthology,dmick/teuthology,michaelsevilla/teuthology,ktdreyer/teuthology,tchaikov/teuthology,ktdreyer/teuthology,SUSE/teuthology,robbat2/teuthology,dmick/teuthology,zhouyuan/teuthology,michaelsevilla/teuthology,caibo2014/teuthology,dreamhost/teuthology,t-miyamae/teuthology,robbat2/teuthology,dreamhost/teuthology,t-miyamae/teuthology,caibo2014/teuthology,yghannam/teuthology,SUSE/teuthology,ceph/teuthology,ivotron/teuthology,ivotron/teuthology,dmick/teuthology,SUSE/teuthology