docs: Modify the error description of the upload component document (#6560)

components/upload/index.en-US.md

@@ -110,7 +110,7 @@ When uploading state change, it returns:
 
 ### How to select albums or folders on mobile devices?
 
-You can set `:accept="null"`
+You can set `:capture="null"`
 
 ### I want to display download links.
 

components/upload/index.zh-CN.md

@@ -111,7 +111,7 @@ cover: https://gw.alipayobjects.com/zos/alicdn/QaeBt_ZMg/Upload.svg
 
 ### 手机设备如何选择相册或文件夹？
 
-你可以设置 `:accept="null"`
+你可以设置 `:capture="null"`
 
 ### 如何显示下载链接？