Update CHANGELOG.md

Author: RKest

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
 
+- Support `suppress_instrumentation` contextmanager from `opentelemetry.instrumentation.utils`.
+
 ## Version 0.5b0 (2025-12-11)
 
 - Ensure log event is written and completion hook is called even when model call results in exception. Put new
@@ -39,4 +41,4 @@ 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))