[Typo]: Missing underscore in unstable_ViewTransition import

[jdharrisnz]

Summary

The unstable_ViewTransition import is missing an underscore in the first code block on the ViewTransition page.

Page

https://react.dev/reference/react/ViewTransition

Details

It should be

import { unstable_ViewTransition as ViewTransition } from 'react';

instead of

import { unstableViewTransition as ViewTransition } from 'react';

[nickwlker]

I addressed it in this PR