Scroll position resets when loading additional data with onMenuScrollToBottom

[nhathoagn]

Description: When using ReactSelect with the onMenuScrollToBottom feature to load additional data, the scroll position is reset to the top of the list each time new data is added. This creates a poor user experience, as users have to scroll back from the beginning instead of continuing from their current scroll position.

Expected behavior: When loading additional data, the scroll position should be maintained, allowing users to continue viewing newly added items without having to scroll back from the top of the list.

Steps to reproduce:

Use ReactSelect with onMenuScrollToBottom to load more data.
Scroll to the bottom of the list to trigger additional loading.
Observe the scroll position resetting to the top of the list when new data is added.