fix item disappearing with scroll in VirtualizedList (#47965)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/47965

Changelog: [General] [Changed] - fix item disappearing with scroll in VirtualizedList

It was caused because the function `computeWindowedRenderLimits` collapsed the current window size to just 1 element. So, users start scroll current window increase from {left:0, right:5 } -> {left:0, right:6 } and after some edge cases the window collapsed to `{left:6, right:6 }` which cause to remove all elements and recreate them later. As a result users have a lot of lags and blank pages.

The diff fixes the collapsing window size to 1 element. Also fix other decreasing `left` position even if windowSize more than current amount of elements.

Reviewed By: NickGerleman

Differential Revision: D66334188

fbshipit-source-id: 2162d00d03d64ab6325c0492d87449051e68a4e9