Fix for online boutique RUM URL

Author: rcastley

local-hosting/proxmox/ubuntu-cloud-k3d.sh

@@ -154,7 +154,7 @@ write_files:
         rum_token: $RUM_TOKEN
         hec_token: $HEC_TOKEN
         hec_url: $HEC_URL
-        url: http://$HOSTNAME:81
+        url: http://frontend
 
 runcmd:
   - systemctl start qemu-guest-agent