Disable test_aten_conv_bf16 to unblock amd ci (#20499)

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### Motivation and Context
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orttraining/orttraining/test/python/orttraining_test_ortmodule_api.py

@@ -6610,6 +6610,8 @@ def test_overridden_softmax_export(softmax_compute_type):
     assert to_value == pytorch_type_to_onnx_dtype(softmax_compute_type), "Cast to attribute is not as expected"
 
 
+# TODO: fix the issue in rocm training, then enable the test.
+@pytest.mark.skip(reason="This test is disabled due to its breaking rocm training cis.")
 def test_aten_conv_bf16():
     class NeuralNetConv(torch.nn.Module):
         def __init__(self):