chore: standards check formatting

What the CI standards job's own --fix pass produced.

.editorconfig has dotnet_style_null_propagation and dotnet_style_coalesce_expression
at error, so the two null ternaries had to go. Both are safe against Unity's ==
overload: InvokeBehaviourOnNetworkObjectParentChanged passes either a literal null
or a spawned object whose transform it has already dereferenced, and SpawnMover is
only ever called with no prefab or a real one.

NativeInterpolatorTests no longer uses anything from System.

Author: NoelStephensUnity

com.unity.netcode.gameobjects/Runtime/Components/NetworkTransform.cs

@@ -4260,7 +4260,7 @@ internal override void InternalOnNetworkObjectParentChanged(NetworkObject parent
             }
 
             // Handle transform space re-parenting transitions for batched transforms.
-            ConvertBatchedInterpolationSpace(m_PositionInterpolator.Parent, parentNetworkObject != null ? parentNetworkObject.transform : null);
+            ConvertBatchedInterpolationSpace(m_PositionInterpolator.Parent, parentNetworkObject?.transform);
 
             InLocalSpace = parentNetworkObject != null;
 

com.unity.netcode.gameobjects/Tests/Runtime/NetworkTransform/NativeInterpolatorTests.cs

@@ -1,4 +1,3 @@
-using System;
 using NUnit.Framework;
 using Unity.Collections;
 using Unity.Mathematics;

com.unity.netcode.gameobjects/Tests/Runtime/NetworkTransform/NetworkTransformSyncModeParityTests.cs

@@ -100,7 +100,7 @@ protected override IEnumerator OnTearDown()
         /// </summary>
         private NetworkObject SpawnMover(ulong ownerClientId = NetworkManager.ServerClientId, GameObject prefab = null)
         {
-            var instance = Object.Instantiate(prefab != null ? prefab : m_MoverPrefab);
+            var instance = Object.Instantiate(prefab ?? m_MoverPrefab);
             var networkObject = instance.GetComponent<NetworkObject>();
             networkObject.NetworkManagerOwner = m_ServerNetworkManager;
             networkObject.SpawnWithOwnership(ownerClientId);