Remove unnecessary reference to this

Change-Id: I1913041fc71169dc69ffd1243663b6304f4dc7ec
diff --git a/core/net/src/test/java/org/onosproject/net/group/impl/GroupManagerTest.java b/core/net/src/test/java/org/onosproject/net/group/impl/GroupManagerTest.java
index 065da4d..d1930eb 100644
--- a/core/net/src/test/java/org/onosproject/net/group/impl/GroupManagerTest.java
+++ b/core/net/src/test/java/org/onosproject/net/group/impl/GroupManagerTest.java
@@ -773,8 +773,8 @@
         }
 
         assertEquals(lastDeviceIdProgrammable, expectedDeviceId);
-        assertTrue((this.groupOperations.containsAll(expectedGroupOps) &&
-                expectedGroupOps.containsAll(groupOperations)));
+        assertTrue(groupOperations.containsAll(expectedGroupOps) &&
+                   expectedGroupOps.containsAll(groupOperations));
 
         groupOperations.clear();
         lastDeviceIdProgrammable = null;