Add changelog

Author: xrmx

CHANGELOG.md

@@ -36,6 +36,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   ([#3894](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3894))
 - `opentelemetry-exporter-richconsole`: Prevent deadlock when parent span is not part of the batch
   ([#3900](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3900))
+- `opentelemetry-instrumentation-aiohttp-server`: delay initialization of tracer, meter and excluded urls to instrumentation for testability
+  ([#3836](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3836))
 
 ## Version 1.38.0/0.59b0 (2025-10-16)