reduced_build_test.onnx_model_with_excluded_ops contains a node using the internal ORT SampleOp, 
which no real model uses as it's an example not an actual operator. Due to this, new models being 
added to test data should not create a scenario where SampleOp accidentally becomes required.

reduced_build_test.onnx_model_with_excluded_ops is intentionally named to not have a '.onnx' extension 
so that the reduced build configuration generation script ignores it, and doesn't add SampleOp as a required
operator to required_ops.config or required_ops_and_types.config.

If the operator reduction runs correctly, SampleOp should always be excluded, and 
reduced_build_test.onnx_model_with_excluded_ops should never be able to be loaded. A unit test verifies
this behavior.
