[RFE] Adding a new nova-compute unit as disabled from OpenStack's perspectiv e

[Felipe Reyes]

There are scenarios where adding a new nova-compute unit may require some extra steps to validate it or enable it to be fully operational (e.g. firewall rules) and if that new nova-compute is registered and enabled to host new instances from the very beginning could lead to disruption on the workloads. Environments that have a high rate of instances created (e.g. CI/CD pipelines) would suffer from this more often than more static workloads.