Update the changelog.

Author: michaelsafyan

instrumentation-genai/opentelemetry-instrumentation-google-genai/CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+- Add automatic instrumentation to tool call functions ([#3446](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3446))
+
 ## Version 0.2b0 (2025-04-28)
 
 - Add more request configuration options to the span attributes ([#3374](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3374))