Mention Node.js support drop as a breaking change

Author: valscion

CHANGELOG.md

@@ -12,6 +12,10 @@ _Note: Gaps between patch versions are faulty, broken or test releases._
 
 ## UNRELEASED
 
+* **Breaking Change**
+  * Remove explicit support for Node versions below 16.20.2 ([#650](https://github.com/webpack-contrib/webpack-bundle-analyzer/pull/650) by [@valscion](https://github.com/valscion))
+    * **NOTE:** `webpack-bundle-analyzer` might still support older Node versions but they are no longer tested against.
+
 * **Improvement**
   * Parse bundles as ES modules based on stats JSON information ([#649](https://github.com/webpack-contrib/webpack-bundle-analyzer/pull/649) by [@eamodio](https://github.com/eamodio))