fix duplicate example names

packages/native-core/src/tree.rs

@@ -178,7 +178,7 @@ impl<'a> TreeMut for TreeMutView<'a> {
 fn set_height(tree: &mut TreeMutView<'_>, node: NodeId, height: u16) {
     let children = {
         let mut node_data_mut = &mut tree.1;
-        let mut node = (&mut node_data_mut).get(node).unwrap();
+        let node = (&mut node_data_mut).get(node).unwrap();
         node.height = height;
         node.children.clone()
     };