add disabled prop (#11188)

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tslint检测时报错
类型“IntrinsicAttributes & IntrinsicClassAttributes<Tree> & Readonly<{ children?: ReactNode; }> & Read...”上不存在属性“disabled”。

components/tree/index.tsx

@@ -59,6 +59,8 @@ export interface TreeProps {
   checkStrictly?: boolean;
   /** 是否支持选中 */
   checkable?: boolean;
+  /** 是否禁用树 */
+  disabled?: boolean;
   /** 默认展开所有树节点 */
   defaultExpandAll?: boolean;
   /** 默认展开指定的树节点 */