Update 2.15 release notes wrt #4378

Author: cowtowncoder

release-notes/VERSION-2.x

@@ -18,7 +18,10 @@ Not yet released
 #4303: `ObjectReader` is not serializable if it's configured for polymorphism
  (reported by @asardaes)
  (fix contributed by Joo-Hyuk K)
-
+#4378: `TextNode.equals()` throws `NullPointerException` when `TextNode`
+  constructed with `null`
+ (reported by @Javed6234)
+ (fix contributed by @pjfanning)
 
 2.15.3 (12-Oct-2023)