Add a changelog entry

Signed-off-by: Lukasz Mierzwa <[email protected]>

Author: prymitive

CHANGELOG.md

@@ -17,6 +17,8 @@ We use *breaking :warning:* to mark changes that are not backward compatible (re
 
 ### Added
 
+- [#](https://github.com/thanos-io/thanos/pull/8582): Sidecar: support --storage.tsdb.delay-compact-file.path Prometheus flag.
+
 ### Changed
 
 - [#8555](https://github.com/thanos-io/thanos/pull/8555): Promu: re-add Darwin and FreeBSD as release platforms