Update tun_singbox_dns

为tun做dns分流

v2rayN/v2rayN/Sample/tun_singbox_dns

@@ -1,5 +1,10 @@
   {
     "servers": [
+      {
+        "tag": "out_dns",
+        "address": "8.8.8.8",
+        "detour": "proxy"
+      },
       {
         "tag": "local",
         "address": "223.5.5.5",
@@ -11,6 +16,11 @@
       }
     ],
     "rules": [
+      {
+        "geosite": "cn",
+        "server": "local",
+        "disable_cache": true
+      },
       {
         "geosite": "category-ads-all",
         "server": "block",
@@ -18,4 +28,4 @@
       }
     ],
     "strategy": "ipv4_only"
-  }
+  }