chore: prepare 6.5.0 release

Author: mfn

CHANGELOG.md

@@ -1,9 +1,11 @@
 CHANGELOG
 =========
 
-[Next release](https://github.com/rebing/graphql-laravel/compare/6.4.0...master)
+[Next release](https://github.com/rebing/graphql-laravel/compare/6.5.0...master)
 --------------
 
+2021-04-03, 6.5.0
+-----------------
 ### Fixed
 - Middleware and methods can be used in class based schemas. [\#724 / jasonvarga](https://github.com/rebing/graphql-laravel/pull/724)\
   This is a follow-up fix for [Support for class based schemas](https://github.com/rebing/graphql-laravel/pull/706)