Update CHANGELOG

Author: kddnewton

CHANGELOG.md

@@ -8,7 +8,7 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/) a
 
 ## [2.4.1] - 2022-05-10
 
-- Fix nested hash patterns from accidentally adding a `then` to their output.
+- [#73](https://github.com/ruby-syntax-tree/syntax_tree/pull/73) - Fix nested hash patterns from accidentally adding a `then` to their output.
 
 ## [2.4.0] - 2022-05-07