Avoid multi-thread issue of encoding the installable Intents to json

ArrayNode uses ArrayList to store data, which is not thread-safe

Change-Id: Id3e54afdf036cbab0909b08b094a2c52124b6bb9
diff --git a/core/common/src/main/java/org/onosproject/codec/impl/IntentCodec.java b/core/common/src/main/java/org/onosproject/codec/impl/IntentCodec.java
index b21ca4e..ed20958 100644
--- a/core/common/src/main/java/org/onosproject/codec/impl/IntentCodec.java
+++ b/core/common/src/main/java/org/onosproject/codec/impl/IntentCodec.java
@@ -68,15 +68,13 @@
         final ArrayNode jsonResources = result.putArray(RESOURCES);
 
         intent.resources()
-                .parallelStream()
-                .forEach(
-                        resource -> {
-                            if (resource instanceof Link) {
-                                jsonResources.add(context.codec(Link.class).encode((Link) resource, context));
-                            } else {
-                                jsonResources.add(resource.toString());
-                            }
-                        });
+                .forEach(resource -> {
+                    if (resource instanceof Link) {
+                        jsonResources.add(context.codec(Link.class).encode((Link) resource, context));
+                    } else {
+                        jsonResources.add(resource.toString());
+                    }
+                });
 
         IntentService service = context.getService(IntentService.class);
         IntentState state = service.getIntentState(intent.key());