Add changelog

Author: xrmx

instrumentation-genai/opentelemetry-instrumentation-openai-v2/CHANGELOG.md

@@ -13,6 +13,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   ([#4028](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/4028))
 - Fix crash with streaming `with_raw_response`
   ([#4033](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/4033))
+- Send `gen_ai.request.seed` instead of openai specific `gen_ai.openai.request.seed`
+  ([#4036](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/4036))
 
 ## Version 2.2b0 (2025-11-25)