Update release notes wrt #311

Author: cowtowncoder

release-notes/CREDITS-2.x

@@ -230,3 +230,10 @@ David Turner (DaveCTurner@github)
 
 * Reported #312: (cbor, smile) Short NUL-only keys incorrectly detected as duplicates
  (2.14.0)
+
+Matthew Pope (popematt@github)
+
+* Contributed #311: (ion) `IonObjectMapper` does not throw JacksonException for some
+  invalid Ion
+ (2.14.0)
+

release-notes/VERSION-2.x

@@ -14,6 +14,8 @@ Modules:
 
 #301: (cbor, smile) Missing configuration methods for format-specific
   parser/generator features
+#311: (ion) `IonObjectMapper` does not throw JacksonException for some invalid Ion
+ (contributed by Matthew P)
 #312: (cbor, smile) Short NUL-only keys incorrectly detected as duplicates
  (reported by David T)