ManagedClusterImportingPhase when adding a new template

[varodrig]

Using this template
https://github.com/stolostron/cluster-templates-manifests/tree/main/hypershift-template

And I tried with my own customizations
https://github.com/varodrig/cluster-templates-manifests
For example (template and cluster creation)

(cluster current status)

[varodrig]

Adding these values in the spec made it work.
cost: 1
skipClusterRegistration: true

[rawagner]

hypershift-template creates cluster without worker nodes. In order to make the Managed Cluster import work, cluster needs to have some workers.
Maybe we could add a detection on ClaaS side and if there are no workers, notify the user with some meaningful message