[FAB-14111] Remove unused function IsMembershipUpdate

The function is no longer used.

Change-Id: Ic19762fd1cfa0d691816220e74977ba9efcce366
Signed-off-by: yacovm <yacovm@il.ibm.com>

orderer/consensus/etcdraft/util.go

@@ -296,27 +296,6 @@ func ConsensusMetadataFromConfigBlock(block *common.Block) (*etcdraft.Metadata,
 	return MetadataFromConfigUpdate(configUpdate)
 }
 
-// IsMembershipUpdate checks whenever block is config block and carries
-// raft cluster membership updates
-func IsMembershipUpdate(block *common.Block, currentMetadata *etcdraft.RaftMetadata) (bool, error) {
-	if !utils.IsConfigBlock(block) {
-		return false, nil
-	}
-
-	metadata, err := ConsensusMetadataFromConfigBlock(block)
-	if err != nil {
-		return false, errors.Wrap(err, "error reading consensus metadata")
-	}
-
-	if metadata != nil {
-		changes := ComputeMembershipChanges(currentMetadata.Consenters, metadata.Consenters)
-
-		return changes.TotalChanges > 0, nil
-	}
-
-	return false, nil
-}
-
 // ConsenterCertificate denotes a TLS certificate of a consenter
 type ConsenterCertificate []byte