fix(tests): update SetSceneNameRequestData call site for new constructor signature

Protocol refresh made sceneName optional and reordered ctor params:
new signature is (newSceneName, canvasUuid?, sceneName?, sceneUuid?).
Update batch test to use named arg so the intent is preserved.

Author: Agash

ObsWebSocket.Tests/ObsWebSocketClientTests.cs

@@ -146,7 +146,7 @@ public async Task CallBatchAsync_ValidRequest_SendsCorrectBatchMessage()
 
         // Define the batch items
         BatchRequestItem request1 = new("GetVersion", null);
-        SetSceneNameRequestData request2Data = new("OldScene", "NewScene");
+        SetSceneNameRequestData request2Data = new("NewScene", sceneName: "OldScene");
         BatchRequestItem request2 = new("SetSceneName", request2Data);
         List<BatchRequestItem> requests = [request1, request2];