private Tensor evaluate(IntermediateOperation op) {
        Tensor tensor = op.evaluateAsConstant(op.type().get()).asTensor();
        return renameToStandardType(op, tensor);
    }
Unit tests for ONNX operators. The number on the test reflects the minimum
opset number for the operations tested.

@author lesters
model-integration/src/test/java/ai/vespa/rankingexpression/importer/onnx/OnnxOperationsTestCase.java