DNM: Temporarily test Ubuntu 20.04

Author: mdbooth

hack/ci/gce-project.sh

@@ -94,7 +94,7 @@ function create_vm {
         --project "$GCP_PROJECT" \
         --zone "$GCP_ZONE" \
         --image-project ubuntu-os-cloud \
-        --image-family ubuntu-2204-lts \
+        --image-family ubuntu-2004-lts \
         --boot-disk-size 200G \
         --boot-disk-type pd-ssd \
         --can-ip-forward \