tree 设置选中节点是否为叶子结点，出现问题

[Cyclone77]

Reproduction link

https://stackblitz.com/edit/angular-bjj7fm?file=src/app/app.component.ts

Steps to reproduce

设置nzTree的nzClick后拿到点击节点赋值给this.activedNode，设置this.activedNode.isLeaf = isLeaf;节点并没有改变。
但是如果在后面改变 this.activedNode.title = ( new Date()) ''; 节点文本，isLeaf 也生效了。

What is expected?

this.activedNode.isLeaf = isLeaf;是可以生效的

What is actually happening?

this.activedNode.isLeaf = isLeaf;并没有生效

Environment	Info
ng-zorro-antd	7.5.1
Browser	google 76

---

例子中点击按钮并没有反应，如果改变代码：

setTreeisLeaf(isLeaf) {
    this.activedNode.isLeaf = isLeaf;
    // this.activedNode.title = (  new Date())   '';
  }

打开注释代码，再次点击就能实现。

[zorro-bot]

Translation of this issue:

Tree Sets whether the selected node is a leaf node, and there is a problem.

Reproduction link

[https://stackblitz.com/edit/angular-bjj7fm?file=src/app/app.component.ts](https://stackblitz.com/edit/angular-bjj7fm?file=src/app/app. Component.ts)

Steps to reproduce

After setting nzTree's nzClick, get the click node assignment to this.activedNode and set this.activedNode.isLeaf = isLeaf; the node has not changed.
But if you change the this.activedNode.title = ( new Date()) ''; node text later, isLeaf will also take effect.

What is expected?

this.activedNode.isLeaf = isLeaf; is valid

What is actually happening?

this.activedNode.isLeaf = isLeaf; does not take effect

Environment	Info
ng-zorro-antd	7.5.1
Browser	google 76

---

In the example, clicking the button does not respond, if you change the code:

setTreeisLeaf(isLeaf) {
    this.activedNode.isLeaf = isLeaf;
    // this.activedNode.title = ( new Date()) '';
  }

Open the comment code and click again to do it.