Fix buck tests

Change-Id: I3d681e6e5c1d3e98c87ccb3d20a619b216ae6133
diff --git a/apps/vtn/vtnweb/src/test/java/org/onosproject/vtnweb/resources/PortPairResourceTest.java b/apps/vtn/vtnweb/src/test/java/org/onosproject/vtnweb/resources/PortPairResourceTest.java
index e436bbe..7335406 100644
--- a/apps/vtn/vtnweb/src/test/java/org/onosproject/vtnweb/resources/PortPairResourceTest.java
+++ b/apps/vtn/vtnweb/src/test/java/org/onosproject/vtnweb/resources/PortPairResourceTest.java
@@ -231,7 +231,7 @@
         String location = "port_pairs/78dcd363-fc23-aeb6-f44b-56dc5e2fb3ae";
 
         Response deleteResponse = wt.path(location)
-                .request(MediaType.APPLICATION_JSON_TYPE)
+                .request(MediaType.APPLICATION_JSON_TYPE, MediaType.TEXT_PLAIN_TYPE)
                 .delete();
         assertThat(deleteResponse.getStatus(),
                    is(HttpURLConnection.HTTP_NO_CONTENT));