Skipping JSDOM version of boolean attribute test

JSDOM lacks support for some attributes, so we'll skip it for now.

See:
 - `async`: jsdom/jsdom#1564
 - `nomodule`: jsdom/jsdom#2475
 - `autofocus`: jsdom/jsdom#3041
 - `inert`: jsdom/jsdom#3605
 - etc...: jestjs/jest#139 (comment)

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

@@ -1,6 +1,16 @@
 import { test } from '../../test';
 
 export default test({
+	// JSDOM lacks support for some of these attributes, so we'll skip it for now.
+	//
+	// See:
+	//  - `async`: https://github.com/jsdom/jsdom/issues/1564
+	//  - `nomodule`: https://github.com/jsdom/jsdom/issues/2475
+	//  - `autofocus`: https://github.com/jsdom/jsdom/issues/3041
+	//  - `inert`: https://github.com/jsdom/jsdom/issues/3605
+	//  - etc...: https://github.com/jestjs/jest/issues/139#issuecomment-592673550
+	skip_mode: ['client'],
+
 	html: `
 	<script nomodule async defer></script>
 	<form novalidate></form>