demo: fix the scroll area is scrolled to the bottom (#47186)

Co-authored-by: heyongqiang <heyongqiang@qtrade.com.cn>

components/list/demo/virtual-list.tsx

@@ -1,6 +1,6 @@
 import React, { useEffect, useState } from 'react';
-import VirtualList from 'rc-virtual-list';
 import { Avatar, List, message } from 'antd';
+import VirtualList from 'rc-virtual-list';
 
 interface UserItem {
   email: string;
@@ -39,7 +39,8 @@ const App: React.FC = () => {
   }, []);
 
   const onScroll = (e: React.UIEvent<HTMLElement, UIEvent>) => {
-    if (e.currentTarget.scrollHeight - e.currentTarget.scrollTop === ContainerHeight) {
+    // Refer to: https://developer.mozilla.org/en-US/docs/Web/API/Element/scrollHeight#problems_and_solutions
+    if (Math.abs(e.currentTarget.scrollHeight - e.currentTarget.scrollTop - ContainerHeight) <= 1) {
       appendData();
     }
   };