Comment 3 for bug 941737

https://bugs.launchpad.net/linaro-image-tools/+bug/638384 seems to be related, talked to Danilo and it seems that force-yes is an appropriate thing to do here. After all, this is just for installing packages into the test image that other things depend on. We don't want to have it blocking waiting for users to approve this, which will never happen. In fact, I thought we were already doing force-yes at one time.