DNS outbound: Set "reject" as the default value for nonIPQuery

https://github.com/XTLS/Xray-core/pull/4903#issuecomment-3091367130

infra/conf/dns_proxy.go

@@ -28,9 +28,7 @@ func (c *DNSOutboundConfig) Build() (proto.Message, error) {
 		config.Server.Address = c.Address.Build()
 	}
 	switch c.NonIPQuery {
-	case "":
-		c.NonIPQuery = "drop"
-	case "drop", "skip", "reject":
+	case "", "reject", "drop", "skip":
 	default:
 		return nil, errors.New(`unknown "nonIPQuery": `, c.NonIPQuery)
 	}