Strange launchpad build failures

I have a snap which refuses to build in launchpad with a strange package error:

Building dependency tree...
Reading state information...
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 openssh-client : Depends: libfido2-1 (>= 1.8.0) but it is not going to be installed
 snapd : Depends: systemd but it is not going to be installed
 udev : Depends: libblkid1 (>= 2.37.2) but 2.36.1-8ubuntu1 is to be installed
E: Unable to correct problems, you have held broken packages.
Install failed

Yaml is here. log is here

I don’t understand why it’s complaining about package installs. I’m using the rust plugin on snapcraft and have specified no build-packages or stage-packages. So this feels like a repo, launchpad or snapcraft issue?

The actual error seems to be further up…

Reading package lists...
W: Failed to fetch http://ftpmaster.internal/ubuntu/dists/jammy/InRelease  Temporary failure resolving 'ftpmaster.internal'
W: Failed to fetch http://ftpmaster.internal/ubuntu/dists/jammy-security/InRelease  Temporary failure resolving 'ftpmaster.internal'
W: Some index files failed to download. They have been ignored, or old ones used instead

Might be temporary… if not, you should perhaps contact the LP team