Replace deprecated JsonObject.readFrom() with Json.parse().asObject

Change-Id: I9e6e5a83edfd2c6abc694c1cc1e939b0b826e980
diff --git a/apps/vtn/vtnweb/src/test/java/org/onosproject/vtnweb/resources/ClassifierResourceTest.java b/apps/vtn/vtnweb/src/test/java/org/onosproject/vtnweb/resources/ClassifierResourceTest.java
index f63cab0..789ae89 100644
--- a/apps/vtn/vtnweb/src/test/java/org/onosproject/vtnweb/resources/ClassifierResourceTest.java
+++ b/apps/vtn/vtnweb/src/test/java/org/onosproject/vtnweb/resources/ClassifierResourceTest.java
@@ -24,6 +24,7 @@
 import static org.onosproject.net.NetTestTools.device;
 import static org.onosproject.net.NetTestTools.did;
 
+import com.eclipsesource.json.Json;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
@@ -93,7 +94,7 @@
 
         final WebResource rs = resource();
         final String response = rs.path("classifiers").get(String.class);
-        final JsonObject result = JsonObject.readFrom(response);
+        final JsonObject result = Json.parse(response).asObject();
         assertThat(result, notNullValue());
     }
 }