docs: update release notes

Author: mohamedawnallah

docs/release-notes/release-notes-0.20.0.md

@@ -71,6 +71,14 @@
 # Technical and Architectural Updates
 ## BOLT Spec Updates
 
+* [Support DNS address in
+  node announcement message](https://github.com/lightningnetwork/lnd/pull/9455):
+  This update allows users to announce their LND node using a DNS address in
+  the node announcement message, by configuring `external-dns-address` field in
+  the LND config file.
+  **Note:** According to BOLT 07, only one DNS address may be announced per
+  node.
+
 ## Testing
 
 ## Database