Update sherpa-onnx /scripts/whisper/test.py

[20246688]

Because the model needs a certain length of input data to work correctly, just like we need a certain amount of time to do something. If the input data is too short, the model may feel unsatisfied, just like we only have a few minutes to complete a task, but actually need more time. So, we added some "virtual" data to make the model feel like it has enough time to handle the task.因为模型需要一定长度的输入数据才能正确工作，就好像我们需要一定长度的时间来做某些事情一样。如果输入数据太短，模型可能会感到不满足，就像是我们只有几分钟的时间来完成一项任务，但实际上需要更多的时间一样，所以我们添加了一些“虚拟”的数据，让模型觉得它有足够的时间来处理任务。

[csukuangfj]

Thank you for your first-time contribution!