Removing workaround

With latest develop fixes (see PR Unity-Technologies/com.unity.netcode.gameobjects#2275 ) this workaround shouldn't be needed anymore

Author: SamuelBellomo

Assets/Tests/Runtime/NetworkedMessageChannelTests.cs

@@ -149,7 +149,6 @@ public IEnumerator NetworkedMessagesAreStillReceivedAfterNetworkManagerShutsDown
 
             m_NbMessagesReceived = 0;
 
-            m_PlayerPrefab.SetActive(false); // to prevent NM from destroying the prefab on shutdown. This flow isn't great and is hackish, should be reworked
             // Shutdown the server and clients
             m_ServerNetworkManager.Shutdown();
             m_ClientNetworkManagers[0].Shutdown();
@@ -159,8 +158,6 @@ public IEnumerator NetworkedMessagesAreStillReceivedAfterNetworkManagerShutsDown
             yield return new WaitWhile(() => m_ClientNetworkManagers[0].ShutdownInProgress);
             yield return new WaitWhile(() => m_ClientNetworkManagers[1].ShutdownInProgress);
 
-            m_PlayerPrefab.SetActive(true); // reactivating after destroy prevention
-
             // Restart the server and clients
             m_ServerNetworkManager.StartHost();
             NetcodeIntegrationTestHelpers.StartOneClient(m_ClientNetworkManagers[0]);