Revert "style: 优化滚动条显示，只有在内容超过显示高度时才会出现 (#1978)" (#2080)

This reverts commit deff31bc5d915e4d3eebf8d625bee02e22e9fe75.

src/components/Table/src/BasicTable.vue

@@ -405,10 +405,6 @@
       width: 100%;
       overflow-x: hidden;
 
-      .ant-table-body {
-        overflow: auto !important;
-      }
-
       &-title {
         display: flex;
         padding: 8px 6px;