fix: Ceilometer compute liveness failureThreshold

Increase failureThreshold of the ceilometer-compute livenessProbe. The ceilometer compute pods could end up in CrashLoopBackOff if the recreation of the NovaComputeNode took a bit longer than usual. This is because the ceilometer-compute is only functional if the socket /var/run/libvirt/virtqemud-sock-ro is available which is provided by the nova-compute pod. During the rebuilding phase of a NovaComputeNode this socket is not available, hence the livenessProbe of ceilometer-compute will fail during this time period.

Note that this is only a quick fix intended to prevent integrationtest failures and a better approach would be to remove the sts while the NCN is being recreated.