dns issues building images in my own GCP project

[bhearsum]

I end up with:

googlecompute.generic_translations_gcp: Provisioning with shell script: scripts/ubuntu-jammy/30-packages.sh
==> googlecompute.generic_translations_gcp: sudo: unable to resolve host packer-65aa977a-59b8-4252-80cc-a5074a4d73eb: Name or service not known
==> googlecompute.generic_translations_gcp:
==> googlecompute.generic_translations_gcp: # init helpers
==> googlecompute.generic_translations_gcp: helpers_dir=${MONOPACKER_HELPERS_DIR:-"/etc/monopacker/scripts"}
==> googlecompute.generic_translations_gcp: + helpers_dir=/etc/monopacker/scripts
==> googlecompute.generic_translations_gcp: for h in ${helpers_dir}/.sh; do
==> googlecompute.generic_translations_gcp: . $h;
==> googlecompute.generic_translations_gcp: done
==> googlecompute.generic_translations_gcp: + for h in ${helpers_dir}/.sh
==> googlecompute.generic_translations_gcp: + . /etc/monopacker/scripts/funcs.sh
==> googlecompute.generic_translations_gcp: #!/bin/bash
==> googlecompute.generic_translations_gcp:
==> googlecompute.generic_translations_gcp: set -ex
==> googlecompute.generic_translations_gcp: ++ set -ex
==> googlecompute.generic_translations_gcp: set +v
==> googlecompute.generic_translations_gcp: ++ set +v
==> googlecompute.generic_translations_gcp: ++ log_dir=/var/log/monopacker/scripts
==> googlecompute.generic_translations_gcp: ++ set -v
==> googlecompute.generic_translations_gcp:
==> googlecompute.generic_translations_gcp: retry apt-get update
==> googlecompute.generic_translations_gcp: + retry apt-get update
==> googlecompute.generic_translations_gcp: + set +e
==> googlecompute.generic_translations_gcp: + local n=0
==> googlecompute.generic_translations_gcp: + local max=5
==> googlecompute.generic_translations_gcp: + true
==> googlecompute.generic_translations_gcp: + apt-get update
==> googlecompute.generic_translations_gcp: Failed to start apt-news.service: Transaction for apt-news.service/start is destructive (systemd-sysusers.service has 'stop' job queued, but 'start' is included in transaction).
==> googlecompute.generic_translations_gcp: See system logs and 'systemctl status apt-news.service' for details.
==> googlecompute.generic_translations_gcp: Failed to start esm-cache.service: Transaction for esm-cache.service/start is destructive (systemd-fsck@dev-disk-by\x2dlabel-UEFI.service has 'stop' job queued, but 'start' is included in transaction).
==> googlecompute.generic_translations_gcp: See system logs and 'systemctl status esm-cache.service' for details.

It seems like this may be somewhat intermittent. I thought I could fix it with:

diff --git a/scripts/ubuntu-jammy/02-grub.sh b/scripts/ubuntu-jammy/02-grub.sh
index 5b7af5a..e042545 100644
--- a/scripts/ubuntu-jammy/02-grub.sh
+++ b/scripts/ubuntu-jammy/02-grub.sh
@@ -32,10 +32,12 @@ cat "${GRUB_INFILE}"
 rm -rf "${TMP_DIR}" 2>/dev/null
 
 # FIXME does not exist?
 # shown here https://launchpad.net/ubuntu/+source/linux-signed/4.15.0-58.64
 # retry apt-get install -y linux-image-$KERNEL_VERSION-dbgsym
 
 # Shutdown and wait forever; packer will consider this script to have finished and
 # start on the next script when it reconnects
+cat /etc/resolv.conf
+echo 'nameserver 8.8.8.8' > /etc/resolv.conf
 shutdown -r now
 while true; do sleep 1; done

...which worked once, but the error kept happening again after that.