For ARO3, updating the azure-cli seems to break commands against the "openshift" resource.
$ az openshift list -o table
The resource type 'openShiftManagedClusters' could not be found in the namespace 'Microsoft.ContainerService' for api version '2019-10-27-preview'. The supported api-versions are '2019-04-30,2019-09-30-preview'.
This affects azure-cli versions 2.5.0 and 2.5.1. Downgrading to 2.4.0 fixes the problem.