Update changelog

Author: thecrypticace

CHANGELOG.md

@@ -32,6 +32,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Fix ordering of parallel variants ([#9282](https://github.com/tailwindlabs/tailwindcss/pull/9282))
 - Handle variants in utility selectors using `:where()` and `:has()` ([#9309](https://github.com/tailwindlabs/tailwindcss/pull/9309))
 - Improve data type analyses for arbitrary values ([#9320](https://github.com/tailwindlabs/tailwindcss/pull/9320))
+- Don't emit generated utilities with invalid uses of theme functions ([#9319](https://github.com/tailwindlabs/tailwindcss/pull/9319))
 
 ## [3.1.8] - 2022-08-05