[BUG] 热词偶尔生效的问题

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Describe the issue

我在使用x-asr-streaming时配置了热词，但是发现热词只有部分时候生效

Steps to reproduce

1. 配置热词和bpe.vocab，使用go-example-api代码
2. 配置相应热词权重，使用x-asr-streaming-480-int8版本
3. 阅读热词内容，发现有时生效，有时不生效

Expected behavior

阅读热词内容，发现有时生效，有时不生效

Environment

• sherpa-onnx version:[v1.13.4]
• OS: Linux-x86 Ubuntu 20.04.6 LTS
• Python version:3.8.18
• onnxruntime version:1.17.1
• GPU (if applicable):
• NPU (if applicable):

Logs