Update release notes wrt #599

Author: cowtowncoder

release-notes/VERSION-2.x

@@ -16,6 +16,8 @@ Active maintainers:
 
 2.20.1 (not yet released)
 
+#599: (cbor) Unable to deserialize stringref-enabled CBOR with ignored properties
+ (reported by Yohei K)
 #601: Jackson subtype Avro schema unions are non-deterministic and therefore
   incompatible with each other
  (reported by Raphael W)
@@ -44,6 +46,8 @@ Active maintainers:
 
 2.19.3 (not yet released)
 
+#599: (cbor) Unable to deserialize stringref-enabled CBOR with ignored properties
+ (reported by Yohei K)
 #601: Jackson subtype Avro schema unions are non-deterministic and therefore
   incompatible with each other
  (reported by Raphael W)