docs: clarify BuildKit note in changelog

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

CHANGELOG.md

@@ -7,7 +7,7 @@
 * `.gitattributes` pinning shell scripts, the Dockerfile and YAML files to LF line endings. With a Windows checkout (`core.autocrlf=true`) the scripts were checked out with CRLF, which made the built image fail to start with `exec /entry.sh: no such file or directory`
 
 ### Changed
-* The Dockerfile now sets the mode of `backup`, `check` and `entry.sh` itself (`COPY --chmod=755`), so the image no longer depends on the build host's umask or on the exec bit of the checked-out scripts. Building now needs BuildKit (default since Docker 23)
+* The Dockerfile now sets the mode of `backup`, `check` and `entry.sh` itself (`COPY --chmod=755`), so the image no longer depends on the build host's umask or on the exec bit of the checked-out scripts. BuildKit is required as before (default since Docker 23)
 
 ### Removed
 * `config-broken.yml` and `docker-compose.test.broken.yml`, replaced by `tests/structure.yml` and the test workflow