Add missing entry to changelog

Author: aantron

doc/CHANGES

@@ -5,6 +5,7 @@ Version 2.7.1 (2022-01-19):
 
   - Emit point data as arrays instead of as lists, to avoid exposing JavaScript
     tooling to large AST structures (#395, Jaap Frolich).
+  - Reporter: look for files relative to Dune workspace root (#369).
 
 Version 2.7.0 (2021-11-23):
 ---------------------------