Update changelog

CHANGELOG.rst

@@ -6,6 +6,14 @@ All notable changes to this project will be documented in this file.
 The format is based on `Keep a Changelog`_,
 and this project adheres to `Semantic Versioning`_.
 
+`4.0.0.dev1`_ - 2024-06-13
+--------------------------
+
+Added
+~~~~~
+
+* Support for entering absences for students in the new coursebook interface.
+
 `4.0.0.dev0`_ - 2024-04-23
 --------------------------