fix: ensure SVG element attributes have case preserved

Author: trueadm

packages/svelte/tests/runtime-runes/samples/svg-attribute-case/_config.js

@@ -1,5 +1,5 @@
 import { test } from '../../test';
 
 export default test({
-	html: `<svg viewBox="0 0 10 10"></svg><svg viewBox="0 0 10 10" xmlns="http://www.w3.org/2000/svg"></svg><svg viewBox=""></svg`
+	html: `<svg viewBox="0 0 10 10"></svg><svg viewBox="0 0 10 10" xmlns="http://www.w3.org/2000/svg"></svg><svg viewBox=""></svg>`
 });