Description of problem: Cannot delete the managed hub cluster from the existing hub cluster

Version-Release number of selected component (if applicable): ACM 2.12.0

How reproducible:

Steps to Reproduce:

1. Enable multiple hub feature via configuring klusterletconfig in managed cluster
2. modify the hubAcceptsClient to false so the the managed cluster will start connecting to the new hub cluster.
3. Then delete the managed cluster from the existing cluster, the cluster cannot be deleted.

Actual results: the cluster cannot be deleted.

Expected results: the cluster should be deleted

Additional info: