Fix Ray 2.7.0 breaking changes (#4964)

tests/test_cuda.py

@@ -79,7 +79,6 @@ def test_predict_sam():
 
 
 @pytest.mark.skipif(not CUDA_IS_AVAILABLE, reason='CUDA is not available')
-@pytest.mark.skipif(True, reason="RayTune Error pyarrow.lib.ArrowInvalid: URI has empty scheme: './runs/tune'")
 def test_model_ray_tune():
     with contextlib.suppress(RuntimeError):  # RuntimeError may be caused by out-of-memory
         YOLO('yolov8n-cls.yaml').tune(use_ray=True,

tests/test_python.py

@@ -41,7 +41,7 @@ def test_model_methods():
     model.to('cpu')
     model.fuse()
     model.clear_callback('on_train_start')
-    model._reset_callbacks()
+    model.reset_callbacks()
 
     # Model properties
     _ = model.names