自建Caddy反代DoH部分

自建自用，有用拿走。自有域名/doh-cf /doh-gg /doh-q9，随意自行修改。

		handle_path /doh-cf* {			rewrite * /dns-query			reverse_proxy https://cloudflare-dns.com {				header_up Host cloudflare-dns.com				header_up -X-Forwarded-For				header_up -X-Real-IP				transport http {					versions 2				}			}			header Cache-Control "public, max-age=300"		}		handle_path /doh-gg* {			rewrite * /dns-query			reverse_proxy https://dns.google {				header_up Host dns.google				header_up -X-Forwarded-For				header_up -X-Real-IP				transport http {					versions 2				}			}			header Cache-Control "public, max-age=300"		}		handle_path /doh-q9* {			rewrite * /dns-query			reverse_proxy https://dns.quad9.net {				header_up Host dns.quad9.net				header_up -X-Forwarded-For				header_up -X-Real-IP				transport http {					versions 2				}			}			header Cache-Control "public, max-age=300"		}