Remove mutating methods in IntentData

Change-Id: I1d9ac694922f4a12b2d94a92b64be2c336c31ae3
diff --git a/core/net/src/main/java/org/onosproject/net/intent/impl/phase/WithdrawRequest.java b/core/net/src/main/java/org/onosproject/net/intent/impl/phase/WithdrawRequest.java
index 8a0709e..a2c3dc0 100644
--- a/core/net/src/main/java/org/onosproject/net/intent/impl/phase/WithdrawRequest.java
+++ b/core/net/src/main/java/org/onosproject/net/intent/impl/phase/WithdrawRequest.java
@@ -64,7 +64,6 @@
             }
         }
 
-        data.setInstallables(stored.get().installables());
-        return Optional.of(new Withdrawing(processor, data));
+        return Optional.of(new Withdrawing(processor, new IntentData(data, stored.get().installables())));
     }
 }