Pluggable Widgets Tools v10.21.1: Update changelog (#128)

This is an automated PR that merges changelog update to master.

Author: weirdwater

packages/pluggable-widgets-tools/CHANGELOG.md

@@ -6,6 +6,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 ## [Unreleased]
 
+## [10.21.1] - 2025-06-13
+
 ### Added
 
 -   We added enzyme-free unit test command in scripts.