fixed changelog

Author: Jayclifford345

CHANGELOG.md

@@ -8,7 +8,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## Unreleased
 
 - Add SynchronousExportingMetricReader for on-demand batch metric export without background threads
-  ([#XXXX](https://github.com/open-telemetry/opentelemetry-python/pull/XXXX))
+  ([#4542](https://github.com/open-telemetry/opentelemetry-python/pull/4542))
 
 ## Version 1.32.0/0.53b0 (2025-04-10)