use style.cssText + adapt test

Author: adiguba

packages/svelte/src/internal/client/dom/elements/style.js

@@ -35,8 +35,7 @@ export function set_style(dom, value, prev_styles, next_styles) {
 			if (next_style_attr == null) {
 				dom.removeAttribute('style');
 			} else {
-				// TODO : dom.style.cssText = next_style_attr;
-				dom.setAttribute('style', next_style_attr);
+				dom.style.cssText = next_style_attr;
 			}
 		}
 		// @ts-expect-error

packages/svelte/tests/runtime-legacy/samples/inline-style-optimisation-bailout/_config.js

@@ -2,7 +2,7 @@ import { ok, test } from '../../test';
 
 export default test({
 	html: `
-		<p style="opacity: 0.5; color: red">color: red</p>
+		<p style="opacity: 0.5; color: red;">color: red;</p>
 	`,
 
 	test({ assert, component, target, window }) {

packages/svelte/tests/runtime-legacy/samples/inline-style-optimisation-bailout/main.svelte

@@ -1,5 +1,5 @@
 <script>
-	export let styles = `color: red`;
+	export let styles = `color: red;`;
 </script>
 
 <p style="opacity: 0.5; {styles}">{styles}</p>

packages/svelte/tests/runtime-runes/samples/dynamic-style-attr/_config.js

@@ -2,7 +2,7 @@ import { test } from '../../test';
 import { flushSync } from 'svelte';
 
 export default test({
-	html: `<div style="background-color: red">Hello world</div><button>Make blue</button`,
+	html: `<div style="background-color: red;">Hello world</div><button>Make blue</button`,
 
 	async test({ assert, target, component }) {
 		const [b1] = target.querySelectorAll('button');
@@ -11,7 +11,7 @@ export default test({
 		});
 		assert.htmlEqual(
 			target.innerHTML,
-			`<div style="background-color: blue">Hello world</div><button>Make blue</button`
+			`<div style="background-color: blue;">Hello world</div><button>Make blue</button`
 		);
 	}
 });

packages/svelte/tests/runtime-runes/samples/dynamic-style-attr/main.svelte

@@ -4,6 +4,6 @@
 	const getColor = () => color;
 </script>
 
-<div style="background-color: {getColor()}">Hello world</div>
+<div style="background-color: {getColor()};">Hello world</div>
 
 <button onclick={() => color = 'blue'}>Make blue</button>