Fix misleading ListItemComponent JSDoc in VirtualizedList types (#58500)

Summary:
I added `ListItemComponent` to these types in #57754 and got the comment wrong. It says the component receives `index` and `separators` "in addition to the data provided to `renderItem`", which reads as if `renderItem` doesn't get them. It does. `_renderElement` in `VirtualizedListCellRenderer.js` passes the same `item`, `index` and `separators` to both.

This fixes that sentence and mentions the one thing that actually is different, which is precedence. When both are set, `ListItemComponent` wins and `_renderElement` logs a warning saying so.

## Changelog:

[INTERNAL] [FIXED] - Fix JSDoc for ListItemComponent in VirtualizedList types

Pull Request resolved: #58500

Test Plan:
Comment-only change in a `.d.ts`, no type changes. Checked the wording against `_renderElement`:

```js
if (ListItemComponent) {
  return (
    <ListItemComponent item={item} index={index} separators={this._separators} />
  );
}
if (renderItem) {
  return renderItem({item, index, separators: this._separators});
}
```

Reviewed By: cortinico

Differential Revision: D120077066

Pulled By: Abbondanzo

fbshipit-source-id: 489321ae950b169c9a985d18220d1ec84114e5fc

Author: aravi365

packages/virtualized-lists/Lists/VirtualizedList.d.ts

@@ -190,8 +190,8 @@ export interface VirtualizedListWithoutRenderItemProps<
 
   /**
    * Each data item is rendered using this element, as an alternative to `renderItem`.
-   * Can be a React Component Class or a render function. In addition to the data provided
-   * to `renderItem`, this receives `index` and `separators` metadata.
+   * It receives the same `item`, `index` and `separators` that `renderItem` gets. If both
+   * are provided, `ListItemComponent` takes precedence and a warning is logged.
    */
   ListItemComponent?:
     React.ComponentType<any> | React.ReactElement | null | undefined;