Upgrade Kryo to 3.0.3.

Possible fix for ONOS-4206.

Now stable on multi-instance.

Change-Id: Icd56759a6223b572d3d166555136d64f26706aaa
diff --git a/pom.xml b/pom.xml
index 15f6a26..83330f4 100644
--- a/pom.xml
+++ b/pom.xml
@@ -321,7 +321,7 @@
             <dependency>
                 <groupId>com.esotericsoftware</groupId>
                 <artifactId>kryo</artifactId>
-                <version>3.0.0</version>
+                <version>3.0.3</version>
             </dependency>
             <dependency>
                 <groupId>com.esotericsoftware</groupId>