fix code style

doc/NEW_WEB_SERVICE.md

 # How to develop a new Web service?
 
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 ([简体中文](NEW_WEB_SERVICE_CN.md)|English)
 
 This document will take Uci service as an example to introduce how to develop a new Web Service. You can check out the complete code [here](../python/examples/pipeline/simple_web_service/web_service.py).

doc/NEW_WEB_SERVICE_CN.md

 # 如何开发一个新的Web Service？
 
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 (简体中文|[English](NEW_WEB_SERVICE.md))
 
 本文档将以 Uci 房价预测服务为例，来介绍如何开发一个新的Web Service。您可以在[这里](../python/examples/pipeline/simple_web_service/web_service.py)查阅完整的代码。