update changelog

Author: RobinMalfait

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Fixed
 
 - Upgrade: Do not migrate declarations that look like candidates in `<style>` blocks ([#18057](https://github.com/tailwindlabs/tailwindcss/pull/18057))
+- Upgrade: Improve `pnpm` workspaces support ([#18065](https://github.com/tailwindlabs/tailwindcss/pull/18065))
 
 ## [4.1.7] - 2025-05-15