Update CHANGELOG.md

Author: ufechner7

CHANGELOG.md

@@ -2,6 +2,12 @@
 SPDX-FileCopyrightText: 2025 Uwe Fechner, Bart van de Lint
 SPDX-License-Identifier: MIT
 -->
+### Unreleased
+#### Changes
+- fix the first line of the Bash test scripts in the tests folder
+- use install before create_sys_image in the test scripts
+- refactoring: added the script `setup_env` that is sourced by the other scripts in the bin folder
+
 ### KiteModels v0.11.6 2026-03-21
 #### Added
 - the functions `copy_examples_3d()` and `install_examples_3d()`