chore: refine plugin.yaml file (#115)

完善插件定义文件。

1. 将 homepage 字段指向 Halo 应用市场的地址。
2. 新增 repo 字段指向源码仓库地址。
3. 新增 issues 字段指向 GitHub issues 地址。

```release-note
None
```

src/main/resources/plugin.yaml

@@ -10,10 +10,12 @@ spec:
  enabled: true
  requires: ">=2.15.0"
  author:
- name: Halo OSS Team
+ name: Halo
  website: https://github.com/halo-dev
  logo: logo.svg
- homepage: https://github.com/halo-dev/plugin-comment-widget
+ homepage: https://www.halo.run/store/apps/app-YXyaD
+ repo: https://github.com/halo-dev/plugin-comment-widget
+ issues: https://github.com/halo-dev/plugin-comment-widget/issues
  displayName: "评论组件"
  description: "为用户前台提供完整的评论解决方案"
  configMapName: plugin-comment-widget-configmap