remove unused cluster node leader

weed/shell/command_cluster_ps.go

@@ -89,9 +89,6 @@ func (c *commandClusterPs) Do(args []string, commandEnv *CommandEnv, writer io.W
 			if node.Rack != "" {
 				fmt.Fprintf(writer, "    Rack: %v\n", node.Rack)
 			}
-			if node.IsLeader {
-				fmt.Fprintf(writer, "    IsLeader: %v\n", true)
-			}
 		}
 	}