add changelog

Signed-off-by: Shi, Stone <[email protected]>

Author: shijiadong2022

CHANGELOG.md

@@ -19,6 +19,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - `opentelemetry-instrumentation-aiokafka` Wrap `AIOKafkaConsumer.getone()` instead of `AIOKafkaConsumer.__anext__`
   ([#2874](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/2874))
+- `opentelemetry-instrumentation-system-metrics` Collect fails on windows because of missing `num_fds`
+  ([#2870](https://github.com/open-telemetry/opentelemetry-python-contrib/issues/2870))
 
 ## Version 1.27.0/0.48b0 ()