Description of problem:

When a MCE cluster is imported to the ACM hub , the ManagedCluster CR is missing "vendor: Openshift" label. 
The MCE cluster is on Bare Metal.
Followed the steps from https://docs.redhat.com/en/documentation/red_hat_advanced_cluster_management_for_kubernetes/2.12/html-single/multicluster_engine_operator_with_red_hat_advanced_cluster_management/index#discover-hosted-acm to import the MCE cluster. The managedcluster CR example given in this document does not suggest to add the label manually.

This affects VolSync as described in the DFBUGS https://issues.redhat.com/browse/DFBUGS-1192 

Workaround: Add the label manually after the managedcluster is imported.

Version-Release number of selected component (if applicable):

ACM 2.13
Openshift 4.18.0-rc.1

How reproducible:

2/2

Steps to Reproduce:

1. Follow the steps 

   https://docs.redhat.com/en/documentation/red_hat_advanced_cluster_management_for_kubernetes/2.12/html-single/multicluster_engine_operator_with_red_hat_advanced_cluster_management/index#discover-hosted-acm to import an MCE cluster to the ACM hub.

1. After importing the cluster , check for the label "vendor: Openshift" in the managedcluster CR
2. ...

Actual results:

The label is missing 

Expected results:

The label should be present

Additional info:
The ACM hub cluster is a hosted cluster.