Text edit scrolls one character left when right-aligned and caret is at furthest right edit point

## Bevy version and features

- main at fb89a8649d9b359e53ffb6e5492ebb7c059ac8af

## What you did

Right aligned text edit, for example in the main version of the multiple_text_inputs example scroll left one character width when the caret is at the furthest right position

## What went wrong

(same control not selected)

(same control with caret a character to left)

Start by reproducing the issue in the multiple_text_inputs example from the main version, using a right-aligned text control and placing the caret at the furthest right edit point. Trace the text-edit scrolling behavior for that caret position. Done means the control no longer scrolls left by one character at the rightmost position, while the reported behavior remains correct when the caret moves left.

Written by the indexing model from the issue text.