Fixed useSyncExternalStoreWithSelector to update memoizedSnapshot o…

…n change (facebook#25968)

## Summary

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A proposed fix for the bug described in
facebook#25967

## How did you test this change?

See the issue linked above, test scenario included in the code sandbox:
https://codesandbox.io/s/fervent-ives-0vm9es?file=/src/App.jsx

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