workbench deploy: detect ubuntu and guide user

deploy-workbench.sh

@@ -390,6 +390,11 @@ prepare_chroot_env() {
         if [ -z "${VERSION_CODENAME:-}" ]; then
                 . /etc/os-release
                 echo "TAKING OS-RELEASE FILE"
+                if [ "${ID}" = "debian" ]; then
+                        echo "ERROR: ubuntu detected, then you are enforced to specify debian variant"
+                        echo "  use for example \`VERSION_CODENAME='bookworm'\` or similar"
+                        exit 1
+                fi
         fi
 
         chroot_path="${ISO_PATH}/chroot"