Update changelog

Author: thecrypticace

CHANGELOG.md

@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Fix preflight border color fallback ([#7288](https://github.com/tailwindlabs/tailwindcss/pull/7288))
 - Correctly parse shadow lengths without a leading zero ([#7289](https://github.com/tailwindlabs/tailwindcss/pull/7289))
+- Don't crash when scanning extremely long class candidates ([#7331](https://github.com/tailwindlabs/tailwindcss/pull/7331))
 
 ## [3.0.18] - 2022-01-28