Webhook support custom proxy (#8760)

* Webhook support custom proxy

* Add glob support on webhook proxy host rules

* fix app.ini.sample

* improve code and app.ini.sample

* update cheetsheet about added webhook options

docs/content/doc/advanced/config-cheat-sheet.en-us.md

@@ -312,6 +312,8 @@ relation to port exhaustion.
 - `DELIVER_TIMEOUT`: **5**: Delivery timeout (sec) for shooting webhooks.
 - `SKIP_TLS_VERIFY`: **false**: Allow insecure certification.
 - `PAGING_NUM`: **10**: Number of webhook history events that are shown in one page.
+- `PROXY_URL`: ****: Proxy server URL, support http://, https//, socks://, blank will follow environment http_proxy/https_proxy
+- `PROXY_HOSTS`: ****: Comma separated list of host names requiring proxy. Glob patterns (*) are accepted; use ** to match all hosts.
 
 ## Mailer (`mailer`)
 

docs/content/doc/advanced/config-cheat-sheet.zh-cn.md

@@ -129,6 +129,8 @@ menu:
 - `DELIVER_TIMEOUT`: 请求webhooks的超时时间，单位秒。
 - `SKIP_TLS_VERIFY`: 是否允许不安全的证书。
 - `PAGING_NUM`: 每页显示的Webhook 历史数量。
+- `PROXY_URL`: ****: 代理服务器网址，支持 http://, https//, socks://, 为空将使用环境变量中的 http_proxy/https_proxy 设置。
+- `PROXY_HOSTS`: ****: 逗号分隔的需要代理的域名或IP地址。支持 * 号匹配符，使用 ** 匹配所有域名和IP地址。
 
 ## Mailer (`mailer`)