known_hosts in t2u container
We need to copy the known hosts file into the container when we create it.
Host key verification failed.
dgit: failed command: ssh 'dgit@push.dgit.debian.org' ': dgit debian git-check dgit-test-dummy ; set -e; cd /dgit/debian/repos; if test -d dgit-test-dummy.git; then echo 1; else echo 0; fi'