something wrong in generating project with Alibaba Sentinel

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**Describe the bug**
When I'm generating a project with the Alibaba Sentinel, I believe the Dubbo annotation "@Reference" should not appear. Additionally, there's an unnecessary class named "FooService" present in the wrong package path "com.alibaba.cloud.demo.sentinel.api". Should I create a PR to fix it?

**To Reproduce**
Steps to reproduce the behavior:
1. Go to 'https://start.aliyun.com'
2. Check in 'Spring Cloud Alibaba Sentinel'
3. Click "Download source code"

**Expected behavior**
1. The Dubbo annotation "@Reference" should not appear in "{{basePackage}}.demos.sentinel"
2. The class named "FooService" is not needed.

**Screenshots**

**Additional context**
Add any other context about the problem here.
e.g. start.aliyun.com website or open source version

Start with the Spring Cloud Alibaba Sentinel option and generated output from https://start.aliyun.com, then trace the corresponding initializer template in this repository. Compare the generated {{basePackage}}.demos.sentinel package and com.alibaba.cloud.demo.sentinel.api contents with the expected behavior; done means the unwanted @Reference annotation and FooService class are absent.

Written by the indexing model from the issue text.