docs: update changelog

Author: jpraynaud

CHANGELOG.md

@@ -23,7 +23,8 @@ As a minor extension, we have adopted a slightly different versioning convention
 
 - DMQ node:
   - Implemented new message id format for the DMQ message to follow specification of the [CIP-0137](https://cips.cardano.org/cip/CIP-0137).
-  - Added support for the DMQ node `0.6.0.0` stable version.
+  - Added support for the DMQ node `0.7.0.0` stable version.
+  - Promoted the DMQ node as stable (beta) on `release-mainnet` and `release-preprod` networks.
   - Added optional support for ledger peers declared with `SRV` records ([CIP-155](https://cips.cardano.org/cip/CIP-0155)).
 
 - Gracefully handle unknown signed entity types across Mithril nodes for improved forward compatibility.