update changelog

Author: RobinMalfait

CHANGELOG.md

@@ -18,6 +18,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - _Upgrade (experimental)_: Rename `drop-shadow` to `drop-shadow-sm` and `drop-shadow-sm` to `drop-shadow-xs` ([#14875](https://github.com/tailwindlabs/tailwindcss/pull/14875))
 - _Upgrade (experimental)_: Rename `rounded` to `rounded-sm` and `rounded-sm` to `rounded-xs` ([#14875](https://github.com/tailwindlabs/tailwindcss/pull/14875))
 - _Upgrade (experimental)_: Rename `blur` to `blur-sm` and `blur-sm` to `blur-xs` ([#14875](https://github.com/tailwindlabs/tailwindcss/pull/14875))
+- _Upgrade (experimental)_: Migrate arbitrary values to modern built-in values ([#14841](https://github.com/tailwindlabs/tailwindcss/pull/14841))
 
 ### Fixed