fix: update upload action of props

resolved #66

Author: wangxueliang

components/upload/interface.jsx

@@ -56,7 +56,7 @@ export const UploadProps = {
   name: PropsTypes.string,
   defaultFileList: PropsTypes.arrayOf(PropsTypes.custom(UploadFile)),
   fileList: PropsTypes.arrayOf(PropsTypes.custom(UploadFile)),
-  action: PropsTypes.string.isRequired,
+  action: PropsTypes.string,
   data: PropsTypes.oneOfType([PropsTypes.object, PropsTypes.func]),
   headers: PropsTypes.object,
   showUploadList: PropsTypes.oneOfType([PropsTypes.bool, ShowUploadListInterface]),