fix(viewer): Unneeded manual internal link; Fix target is in LaTeX

[yhx-12243]

Svelte has automatically internal link mechanism, so the manual implementation is not necessary and it is also wrong: When user click internal link just in LaTeX, it will goto undefined. So we simply delete it and it works well.

web/packages/viewer/src/components/Shared/Typeset.svelte

Lines 51 to 54 in c571c93

	link.addEventListener('click', e => {
	e.preventDefault()
	goto((e.target as HTMLAnchorElement).href)
	})

e.target is not necessary an <a>, it may deep inside a KaTeX node.