update changelog

CHANGELOG.md

@@ -7,7 +7,8 @@
 * Fix reactivity with imported values that are then mutated ([#4555](https://github.com/sveltejs/svelte/issues/4555))
 * Do not display a11y warning about missing `href` for `<a>` with `name` or `id` ([#4697](https://github.com/sveltejs/svelte/issues/4697))
 * Disable infinite loop guard inside generators ([#4698](https://github.com/sveltejs/svelte/issues/4698))
-* Display a11y warning for `href="javascript:..."` ([#4733](https://github.com/sveltejs/svelte/pull/4733))
+* Display `a11y-invalid-attribute` warning for `href="javascript:..."` ([#4733](https://github.com/sveltejs/svelte/pull/4733))
+* Implement `a11y-img-redundant-alt` warning ([#4750](https://github.com/sveltejs/svelte/pull/4750))
 * Fix variable name conflict with component called `<Anchor>` ([#4768](https://github.com/sveltejs/svelte/issues/4768))
 
 ## 3.21.0