Update CHANGELOG.md

Author: RKest

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

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Ensure log event is written and completion hook is called even when model call results in exception. Put new
 log event (` gen_ai.client.inference.operation.details`) behind the flag `OTEL_SEMCONV_STABILITY_OPT_IN=gen_ai_latest_experimental`.
 Ensure same sem conv attributes are on the log and span. Fix an issue where the instrumentation would crash when a pydantic.BaseModel class was passed as the response schema ([#3905](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3905)).
+- Support `suppress_instrumentation` contextmanager from `opentelemetry.instrumentation.utils`.
 
 ## Version 0.4b0 (2025-10-16)
 
@@ -36,4 +37,4 @@ span attribute `gen_ai.response.finish_reasons` is empty ([#3417](https://github
   ([#3298](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3298))
 
 Create an initial version of Open Telemetry instrumentation for github.com/googleapis/python-genai.
-([#3256](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3256)) 
+([#3256](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3256))