No valid instance count value found

### Description

running a cou plan on an openstack bobcat the error is
[ERROR] No valid instance count value found in the result of instance-count action running on 'nova-compute/4': {'return-code': 0}

the openstack is a full virtaul overcloud i.e. I created it as a model into another openstack

### Charm revision

charmed-openstack-upgrader 2.2.3 367 latest/stable

### Juju version

juju 3.6.11 32911 3/stable

### Cloud

OpenStack

### Expected behaviour

cou plan should give me a plan

### Reproduce / Test

after deploying openstack by the bundle above, simply run
cou plan

### Notes & References

this is my bundle
https://dpaste.com/3VW5L9PGK

this is my model-config
https://dpaste.com/DSZJPAHK8

and this is the error log
https://dpaste.com/38MZJE5JM

Start with the cou plan path that runs the instance-count action, then review the linked error log, bundle, and model-config for the OpenStack Bobcat deployment. Reproduce the reported setup and determine why the action result contains only {'return-code': 0}; done means cou plan produces a valid plan for this deployment.

Written by the indexing model from the issue text.