update radio group demo

components/radio/__tests__/__snapshots__/demo.test.js.snap

@@ -493,7 +493,7 @@ exports[`renders ./components/radio/demo/radiogroup-more.md correctly 1`] = `
 </div>
 `;
 
-exports[`renders ./components/radio/demo/radiogroup-optional.md correctly 1`] = `
+exports[`renders ./components/radio/demo/radiogroup-options.md correctly 1`] = `
 <div>
   <div
     class="ant-radio-group"

components/radio/demo/radiogroup-optional.md → components/radio/demo/radiogroup-options.md

@@ -7,11 +7,15 @@ title:
 
 ## zh-CN
 
-通过配置参数来控制渲染单选框。
+通过配置 `options` 参数来渲染单选框。
+
+> `2.9.0` 之后支持。
 
 ## en-US
 
-Render radios by configuring parameters.
+Render radios by configuring `options`.
+
+> support after `2.9.0`.
 
 ```jsx
 import { Radio } from 'antd';
@@ -65,4 +69,4 @@ class App extends React.Component {
 }
 
 ReactDOM.render(<App />, mountNode);
-```
+```