Update changelog

Author: infctr

CHANGELOG.md

@@ -10,3 +10,5 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
 - New option to `interface` rule: `requiredFirst` - if `true`, enforce optional properties to come after required ones.
+
+[0.9.0]: https://github.com/infctr/eslint-plugin-typescript-sort-keys/compare/v0.8.0...v0.9.0