Comment 31 for bug 1659719

And bionic:

mwhudson@anduril:~$ ssh ubuntu@10.187.142.63 "sh -c 'dpkg-query -W libpam-modules; type go '"
libpam-modules:amd64 1.1.8-3.6ubuntu2.18.04.1
go: not found
mwhudson@anduril:~$ lxc exec test-pam-bionic -- apt install -y libpam-modules/bionic-proposed
Reading package lists... Done
Building dependency tree
Reading state information... Done
Selected version '1.1.8-3.6ubuntu2.18.04.2' (Ubuntu:18.04/bionic-proposed [amd64]) for 'libpam-modules'
Selected version '1.1.8-3.6ubuntu2.18.04.2' (Ubuntu:18.04/bionic-proposed [amd64]) for 'libpam-modules-bin' because of 'libpam-modules'
...
mwhudson@anduril:~$ ssh ubuntu@10.187.142.63 "sh -c 'dpkg-query -W libpam-modules; type go '"
libpam-modules:amd64 1.1.8-3.6ubuntu2.18.04.2
go is /snap/bin/go

The autopkgtest failure, dovecot/armhf looks to be a flake. I've retried it anyway to see if it passes now.