chore: add CHANGELOG entry for aiokafka 0.13 compatibility fix

Author: dorlib

CHANGELOG.md

@@ -36,6 +36,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   ([#4302](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/4302))
 - `opentelemetry-instrumentation-grpc`: Fix bidirectional streaming RPCs raising `AttributeError: 'generator' object has no attribute 'add_done_callback'`
   ([#4259](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/4259))
+- `opentelemetry-instrumentation-aiokafka`: Fix compatibility with aiokafka 0.13 by calling
+  `_key_serializer`/`_value_serializer` directly instead of the internal `_serialize` method
+  whose signature changed in 0.13 from `(topic, key, value)` to `(key, value, headers)`
 
 ### Breaking changes