Update changelog for 7.3.0 release

CHANGELOG.md

@@ -6,6 +6,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ## [Unreleased]
 
+## [7.3.0] - released 2018-11-13
+
 ### Changed
 - Moved  the `finalizeScopes()` call from `validateAuthorizationRequest` method to the `completeAuthorizationRequest` method so it is called just before the access token is issued (PR #923)
 
@@ -420,7 +422,8 @@ Version 5 is a complete code rewrite.
 
 - First major release
 
-[Unreleased]: https://github.com/thephpleague/oauth2-server/compare/7.2.0...HEAD
+[Unreleased]: https://github.com/thephpleague/oauth2-server/compare/7.3.0...HEAD
+[7.3.0]: https://github.com/thephpleague/oauth2-server/compare/7.2.0...7.3.0
 [7.2.0]: https://github.com/thephpleague/oauth2-server/compare/7.1.1...7.2.0
 [7.1.1]: https://github.com/thephpleague/oauth2-server/compare/7.1.0...7.1.1
 [7.1.0]: https://github.com/thephpleague/oauth2-server/compare/7.0.0...7.1.0