Fix ManagedCluster CRD confusing points

[a13x5]

I noticed several issues with the ManagedCluster CR:

1. Name ManagedCluster clashes with the resource ManagedCluster of containerservice.azure.com/v1api20210501 which is a part of Azure provider. This means that user can't execute kubectl get managedcluster and has to user the full name kubectl get managedcluster.v1alpha1.hmc.mirantis.com
2. Short names of the ManagedCluster are hmc-deploy and deploy which make confusion even more.

The task

Replace short names to be similar to the full name. In the docs if ManagedCluster resource is mentioned in scope of kubectl commands it should referenced by a full name with group and version (managedcluster.v1alpha1.hmc.mirantis.com).

[a13x5]

Reopen, since docs aren't ready