Remove "public" to follow our convention

Change-Id: Ic5fa8744cbcb4c704780c8467ae0f31fce3327ce
diff --git a/core/api/src/main/java/org/onosproject/store/service/Serializer.java b/core/api/src/main/java/org/onosproject/store/service/Serializer.java
index 32ae585..5e1b84e 100644
--- a/core/api/src/main/java/org/onosproject/store/service/Serializer.java
+++ b/core/api/src/main/java/org/onosproject/store/service/Serializer.java
@@ -44,7 +44,7 @@
      * @param kryo kryo namespace
      * @return Serializer instance
      */
-    public static Serializer using(KryoNamespace kryo) {
+    static Serializer using(KryoNamespace kryo) {
         return new Serializer() {
             @Override
             public <T> byte[] encode(T object) {
@@ -57,4 +57,4 @@
             }
         };
     }
-}
\ No newline at end of file
+}