update release notes

Author: cowtowncoder

release-notes/VERSION-2.x

@@ -20,6 +20,7 @@ NOTE: Jackson 3.x components rely on 2.x annotations; there are no separate
  (requested by @moutyque)
 #294: Drop patch number from version for 2.20 and later (no more 2.20.0)
 #296: Drop Java 6 compatibility for 2.20 (Java 8 baseline)
+- Dropped Gradle BOM alignment configuration (as 2.20+ will be used by Jackson 3.x)
 
 2.19.1 (13-Jun-2025)