added windows's cmd's creation_flag

src/network/tun_win.rs

@@ -1,5 +1,6 @@
 use sdlan_sn_rs::utils::{ip_to_string, net_bit_len_to_mask};
 use std::io::{Error, ErrorKind};
+use std::os::windows::process::CommandExt;
 use std::process::Command;
 use std::sync::Arc;
 use wintun;
@@ -53,6 +54,7 @@ impl  Iface {
         let mut cmd = Command::new("netsh");
         debug!("name={}, addr={}, mask={}", self.name, ip, netbit);
         let command = cmd
+            .creation_flags(0x08000000)
             .arg("interface")
             .arg("ip")
             .arg("set")