[SearchTree]: 下拉面板高度不好限制

[wangwei88]

[wj0990]

@wangwei88 组件有个 treeProps 参数 可以向子集添加样式

<SearchTree
     multiple={false}
     style={{ width: 200 }}
     allowClear={true}
     onSearch={(searchValue)=>console.log('SearchTree-> SearchTreeOption',searchValue)}
     onChange={(selectd, selectedAll,  isChecked)=>console.log('SearchTree-> onChange', selectd, selectedAll, isChecked)}
     options={data}
     placeholder="请选择选项"
     treeProps={{ style:{ height:100, overflow:'scroll' }}}
 />