Removing nova-compute with ovn-chassis related doesn't remove chassis from OVN

[macchese]

my environment is a jammy openstack bundle 2023.2 with
ovn-central 3.09/stable
ovn-chassis 3.09/stable

After removing a compute-node with a related ovn-chassis this node is not removed from OVN chassis.

how to reproduce:
1) check if the node you want to remove is a chassis
ubuntu@juju:~$ juju exec --unit ovn-central/x 'ovn-sbctl show' where x is the ovnsb_db leader
your should display your node

3) check the juju status of your node (my machine is 7):
ubuntu@juju:~$ juju status machine 7 |egrep "nova-compute/|ovn-chassis/"
nova-compute/13* active idle 7 192.168.6.101 Unit is ready
  ovn-chassis/46 active idle 192.168.6.101 Unit is ready

2) remove the node according to https://docs.openstack.org/charm-guide/latest/admin/ops-scale-back-nova-compute.html:
ubuntu@juju:~$ juju run nova-compute/13 disable
ubuntu@juju:~$ juju run nova-compute/13 remove-from-cloud
ubuntu@juju:~$ juju remove-unit nova-compute/13

3) check if units nova-compute/13 and ovn-chassis/46 are removed:
ubuntu@juju:~$ juju status nova-compute

4) check if your node is removed from the router:
ubuntu@juju:~$ juju exec --unit ovn-central/x 'ovn-sbctl show' where x is the ovnsb_db leader

At this point my removed node is still present in the chassis list. Same iusse with an external gateway, the node remains into the list of gateways

[macchese (max-liccardo)]

in order to remove chassis from OVN N/S database I executed on every removed compute node:

apt -y purge nova-common ovn-common neutron-ovn-metadata-agent neutron-common
rm -fr /etc/nova /var/lib/nova/instances /etc/ovn

If the removed compute node is also a gateway chassis one needs to remove the router port