update CHANGELOG.md

Author: herin049

CHANGELOG.md

@@ -14,6 +14,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - `opentelemetry-sdk`: Add `service` resource detector support to declarative file configuration via `detection_development.detectors[].service`
   ([#5003](https://github.com/open-telemetry/opentelemetry-python/pull/5003))
+- `opentelemetry-exporter-otlp-json-common`: add 'opentelemetry-exporter-otlp-json-common' package for OTLP JSON exporters
+  ([#4996](https://github.com/open-telemetry/opentelemetry-python/pull/4996))
 
 ## Version 1.41.0/0.62b0 (2026-04-09)