Add credits to changelog

CHANGELOG

@@ -32,7 +32,7 @@ v 8.2.0 (unreleased)
   - Add "added", "modified" and "removed" properties to commit object in webhook
   - Rename "Back to" links to "Go to" because its not always a case it point to place user come from
   - Allow groups to appear in the search results if the group owner allows it
-  - Add email notification to former assignee upon unassignment
+  - Add email notification to former assignee upon unassignment (Adam Lieskovský)
   - New design for project graphs page
   - Remove deprecated dumped yaml file generated from previous job definitions
   - Fix incoming email config defaults