docs: add changelog for PR 12264

changes/e5.4.1.en.md

@@ -19,3 +19,5 @@
 - [#12250](https://github.com/emqx/emqx/pull/12250) Resolved an issue where the `file_transfer` configuration's `secret_access_key` value was erroneously being updated to masked stars (`*****`), ensuring that the original key value remains unaltered and secure.
 
 - [#12256](https://github.com/emqx/emqx/pull/12256) Fixed an issue that prevented establishing connections to MySQL resources without a password.
+
+- [#12264](https://github.com/emqx/emqx/pull/12264) Fix rolling upgrade when replica nodes join cluster with core nodes prior to version 5.4.

changes/v5.4.1.en.md

@@ -11,3 +11,5 @@
 - [#12246](https://github.com/emqx/emqx/pull/12246) Stopped exposing port 11883 by default in Docker and removed it from Helm charts, as this port is no longer in use. 
 
 - [#12249](https://github.com/emqx/emqx/pull/12249) Fixed an issue in the `/configs` API where attempting to modify a read-only configuration value resulted in a garbled response message.
+
+- [#12264](https://github.com/emqx/emqx/pull/12264) Fix rolling upgrade when replica nodes join cluster with core nodes prior to version 5.4.