chore: adapt changelog

Author: maltesander

CHANGELOG.md

@@ -18,6 +18,8 @@ All notable changes to this project will be documented in this file.
 - Document Helm deployed RBAC permissions and remove unnecessary permissions ([#820]).
 - Internal operator refactoring: introduce dereference() and validate() steps in the reconciler ([#836]).
 - test: Bump vector-aggregator to 0.55.0, replace /graphql call with gRPC call ([#840]).
+- BREAKING: Removed product-config machinery. This is a breaking change in terms of configuration.
+  Users relying on the product-config `properties.yaml` file have to set these properties via the CRD ([#842]).
 
 ### Removed
 
@@ -31,6 +33,7 @@ All notable changes to this project will be documented in this file.
 [#836]: https://github.com/stackabletech/opa-operator/pull/836
 [#838]: https://github.com/stackabletech/opa-operator/pull/838
 [#840]: https://github.com/stackabletech/opa-operator/pull/840
+[#842]: https://github.com/stackabletech/opa-operator/pull/842
 
 ## [26.3.0] - 2026-03-16