docs: improve upload demos (#35104)

* docs: improve upload demos

* Update drag-sorting.md

components/upload/demo/avatar.md

@@ -84,12 +84,5 @@ class Avatar extends React.Component {
   }
 }
 
-export default () => <Avatar />;
-```
-
-```css
-.avatar-uploader > .ant-upload {
-  width: 128px;
-  height: 128px;
-}
+export default Avatar;
 ```

components/upload/demo/drag-sorting.md

@@ -135,7 +135,7 @@ const DragSortingUpload = () => {
   );
 };
 
-export default () => <DragSortingUpload />;
+export default DragSortingUpload;
 ```
 
 ```css

components/upload/demo/file-type.md

@@ -35,7 +35,7 @@ function getBase64(file) {
   });
 }
 
-class PicturesWall extends React.Component {
+class App extends React.Component {
   state = {
     previewVisible: false,
     previewImage: '',
@@ -139,5 +139,5 @@ class PicturesWall extends React.Component {
   }
 }
 
-export default () => <PicturesWall />;
+export default App;
 ```

components/upload/demo/fileList.md

@@ -25,7 +25,7 @@ You can gain full control over filelist by configuring `fileList`. You can accom
 import { Upload, Button } from 'antd';
 import { UploadOutlined } from '@ant-design/icons';
 
-class MyUpload extends React.Component {
+class App extends React.Component {
   state = {
     fileList: [
       {
@@ -70,5 +70,5 @@ class MyUpload extends React.Component {
   }
 }
 
-export default () => <MyUpload />;
+export default App;
 ```

components/upload/demo/picture-card.md

@@ -26,7 +26,7 @@ function getBase64(file) {
   });
 }
 
-class PicturesWall extends React.Component {
+class App extends React.Component {
   state = {
     previewVisible: false,
     previewImage: '',
@@ -119,5 +119,5 @@ class PicturesWall extends React.Component {
   }
 }
 
-export default () => <PicturesWall />;
+export default App;
 ```

components/upload/demo/upload-png-only.md

@@ -18,7 +18,7 @@ import React, { useState } from 'react';
 import { Upload, Button, message } from 'antd';
 import { UploadOutlined } from '@ant-design/icons';
 
-const Uploader = () => {
+const App = () => {
   const props = {
     beforeUpload: file => {
       const isPNG = file.type === 'image/png';
@@ -38,5 +38,5 @@ const Uploader = () => {
   );
 };
 
-export default () => <Uploader />;
+export default App;
 ```

components/upload/demo/upload-with-aliyun-oss.md

@@ -112,7 +112,7 @@ class AliyunOSSUpload extends React.Component {
   }
 }
 
-const FormPage = () => (
+const App = () => (
   <Form labelCol={{ span: 4 }}>
     <Form.Item label="Photos" name="photos">
       <AliyunOSSUpload />
@@ -120,5 +120,5 @@ const FormPage = () => (
   </Form>
 );
 
-export default () => <FormPage />;
+export default App;
 ```