test

Adding the test for this fix.

Author: NoelStephensUnity

com.unity.netcode.gameobjects/Tests/Runtime/AttachableBehaviourTests.cs

@@ -55,7 +55,7 @@ protected override void OnServerAndClientsCreated()
             attachableNetworkObject.SetOwnershipStatus(NetworkObject.OwnershipStatus.Transferable);
 
             // The target prefab that the source prefab will attach
-            // will be parented under the target prefab.
+            // to will be parented under the target prefab.
             m_TargetNodePrefabA = CreateNetworkObjectPrefab("TargetA");
             m_TargetNodePrefabB = CreateNetworkObjectPrefab("TargetB");
             var sourceChild = new GameObject("SourceChild");
@@ -676,10 +676,13 @@ internal class TestAttachable : AttachableBehaviour
             public GameObject DefaultParent => m_DefaultParent;
             public AttachState State => m_AttachState;
 
+            public bool DestroyWithScene;
+
             public override void OnNetworkSpawn()
             {
                 AttachStateChange += OnAttachStateChangeEvent;
                 name = $"{name}-{NetworkManager.LocalClientId}";
+                NetworkObject.DestroyWithScene = DestroyWithScene;
                 base.OnNetworkSpawn();
             }
 
@@ -780,9 +783,16 @@ public bool CheckForState(bool checkAttached, bool checkEvent)
         /// </summary>
         internal class TestNode : AttachableNode
         {
+            public bool DestroyWithScene;
             public bool OnAttachedInvoked { get; private set; }
             public bool OnDetachedInvoked { get; private set; }
 
+            public override void OnNetworkSpawn()
+            {
+                NetworkObject.DestroyWithScene = DestroyWithScene;
+                base.OnNetworkSpawn();
+            }
+
             public bool IsAttached(AttachableBehaviour attachableBehaviour)
             {
                 return m_AttachedBehaviours.Contains(attachableBehaviour);