update changelog

Author: mohammadVatandoost

opentelemetry-sdk/CHANGELOG.md

@@ -69,6 +69,7 @@ Released 2025-Mar-21
   Custom exporters will need to internally synchronize any mutable state, if applicable.
 
 - **Breaking** The `shutdown_with_timeout` method is added to MetricExporter trait. This is breaking change for custom `MetricExporter` authors.
+- **Breaking** The `shutdown_with_timeout` method is added to MetricReader trait. This is breaking change for custom `MetricReader` authors.
 - Bug Fix: `BatchLogProcessor` now correctly calls `shutdown` on the exporter
   when its `shutdown` is invoked.