Update changelog

Author: adamwathan

CHANGELOG.md

@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - New `layers` mode for `purge` ([#2288](https://github.com/tailwindlabs/tailwindcss/pull/2288))
 - New `font-variant-numeric` utilities ([#2305](https://github.com/tailwindlabs/tailwindcss/pull/2305))
 - New `place-items`, `place-content`, `place-self`, `justify-items`, and `justify-self` utilities ([#2306](https://github.com/tailwindlabs/tailwindcss/pull/2306))
+- Support configuring variants as functions ([#2309](https://github.com/tailwindlabs/tailwindcss/pull/2309))
 
 ### Deprecated