Deleting a user doesn't reevaluate the access of the devices it owned

[julsemaan]

Describe the bug
When you delete a user via the admin, then the nodes he owns are unregistered but their access isn't reevaluated which leaves devices online although they are now unregistered

To Reproduce

1. Register a device under any user
2. Go in Users->click on the user details->Hit delete
3. Device is unreg but no access reevaluation was done

Expected behavior
After unregistering the device, access reevaluation should be performed

[jrouzierinverse]

This scenario cannot happen as explained.
When a user is deleted all their nodes are deleted from the database.
https://github.com/inverse-inc/packetfence/blob/devel/db/pf-schema-10.2.0.sql#L191
Obviously, we still need to unreg and reevaluate before the deletion.
Should we warn that the user has registered nodes on the system before letting them be deleted?

[julsemaan]

We can perform a unassignement of the nodes of the user (put them back on the default user), block the deletion or do the access reevaluation.

Any of the 3 are fine with me, if they are unassigned, just make sure proper warnings are in place so the user understands what is about to happen