Update changelog

Author: Sephster

CHANGELOG.md

@@ -6,6 +6,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ## [Unreleased]
 
+## [8.1.1] - released 2020-07-01
+
 ### Fixed
 - If you provide a valid redirect_uri with the auth code grant and an invalid scope, the server will use the given 
 redirect_uri instead of the default client redirect uri (PR #1126)
@@ -497,7 +499,8 @@ Version 5 is a complete code rewrite.
 
 - First major release
 
-[Unreleased]: https://github.com/thephpleague/oauth2-server/compare/8.1.0...HEAD
+[Unreleased]: https://github.com/thephpleague/oauth2-server/compare/8.1.1...HEAD
+[8.1.1]: https://github.com/thephpleague/oauth2-server/compare/8.1.0...8.1.1
 [8.1.0]: https://github.com/thephpleague/oauth2-server/compare/8.0.0...8.1.0
 [8.0.0]: https://github.com/thephpleague/oauth2-server/compare/7.4.0...8.0.0
 [7.4.0]: https://github.com/thephpleague/oauth2-server/compare/7.3.3...7.4.0