Update changelog

CHANGELOG.md

@@ -43,6 +43,9 @@
 * `console.*()` calls in tests are now always intercepted by default. To show them use `--nocapture`. When shown they are always printed in-place instead of after test results, analogous to `cargo test`.
   [#4356](https://github.com/rustwasm/wasm-bindgen/pull/4356)
 
+* Deprecation warning when using an async function as a constructor
+  [#4402](https://github.com/rustwasm/wasm-bindgen/pull/4402)
+
 ### Fixed
 
 - Fixed using [JavaScript keyword](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Lexical_grammar#keywords) as identifiers not being handled correctly.