Comment 7 for bug 2004551

I'm seeing something that looks just like this in a dep8 mantic test run, where openssh-server is upgraded while preparing the testbed and postinst fails[1]:

977s Preparing to unpack .../openssh-sftp-server_1%3a9.3p1-1ubuntu1_amd64.deb ...
977s Unpacking openssh-sftp-server (1:9.3p1-1ubuntu1) over (1:9.2p1-2ubuntu3) ...
977s Preparing to unpack .../openssh-server_1%3a9.3p1-1ubuntu1_amd64.deb ...
977s Warning: Stopping ssh.service, but it can still be activated by:
977s ssh.socket
977s Unpacking openssh-server (1:9.3p1-1ubuntu1) over (1:9.2p1-2ubuntu3) ...
(...)
992s Setting up openssh-server (1:9.3p1-1ubuntu1) ...
993s rescue-ssh.target is a disabled or a static unit not running, not starting it.
993s Could not execute systemctl: at /usr/bin/deb-systemd-invoke line 145.
993s dpkg: error processing package openssh-server (--configure):
993s installed openssh-server package post-installation script subprocess returned error exit status 1
(...)
1016s Errors were encountered while processing:
1016s openssh-server

1. https://autopkgtest.ubuntu.com/results/autopkgtest-mantic-ahasenack-samba-kb5028166/mantic/amd64/s/samba/20230720_195603_95cad@/log.gz