chore: update changes

changes/v5.0.12-en.md

@@ -34,6 +34,8 @@ Please note, the request body of `/bridges` API to configure MQTT brdige is chan
 
 - Users can define the `externalTrafficPolicy` of service in EMQX Helm Chart [#9527](https://github.com/emqx/emqx/pull/9527).
 
+- Return `204` instead of `200` for `POST /gateway/lwm2m/clients/{clientid}/{read,write,observe}` [#9480](https://github.com/emqx/emqx/pull/9480).
+
 ## Bug fixes
 
 - Fix that the obsolete SSL files aren't deleted after the ExHook config update [#9432](https://github.com/emqx/emqx/pull/9432).

changes/v5.0.12-zh.md

@@ -33,6 +33,8 @@ v5.0.11 或更早版本创建的配置文件，在新版本中会被自动转换
 
 - 用户可以在 EMQX Helm Chart 中自定义 service 资源的 `externalTrafficPolicy` [#9527](https://github.com/emqx/emqx/pull/9527)。
 
+- Return `204` instead of `200` for `POST /gateway/lwm2m/clients/{clientid}/{read,write,observe}` [#9480](https://github.com/emqx/emqx/pull/9480).
+
 ## 修复
 
 - 修复 ExHook 更新 SSL 相关配置后，过时的 SSL 文件没有被删除的问题 [#9432](https://github.com/emqx/emqx/pull/9432)。