update changelog

Author: Conduitry

CHANGELOG.md

@@ -5,6 +5,7 @@
 * Avoid recreating DOM elements during hydration ([#1067](https://github.com/sveltejs/svelte/issues/1067))
 * Support passing CSS custom properties to component ([#5628](https://github.com/sveltejs/svelte/issues/5628))
 * Support `:global()` as part of compound CSS selectors ([#6222](https://github.com/sveltejs/svelte/issues/6222))
+* Fix setting boolean attributes on custom elements ([#5951](https://github.com/sveltejs/svelte/issues/5951))
 * Add missing function overload for `derived` to allow explicitly setting an initial value for non-async derived stores ([#6172](https://github.com/sveltejs/svelte/pull/6172))
 * Fix scope leak when updating an `{#await}` block ([#6173](https://github.com/sveltejs/svelte/issues/6173))
 * Pass full markup source to `script`/`style` preprocessors ([#6169](https://github.com/sveltejs/svelte/pull/6169))