can add node from the same cluster as remote replication cluster

steps:
1.cluster with 2 nodes: node1, node2
two buckets: bucket1, bucket3
2. create cluster reference as: bucket1/node1 - > bucket2/node2

observation:
when try to add cluster reference like as bucket1/node1 - > bucket2/node1, the expected error appears:

Attention - Cluster reference to the same cluster already exists under the name `10.5.2.13`

expected result:
the user should not be able to add reference to node from the same cluster.