[fix] variable didn't exist anymore

renew_from_cube.py

@@ -52,9 +52,10 @@ def from_cube():
 
     sys.stdout.flush()
 
-    print("Critical part: reloading vpn using '%s'" % command)
+    restart_command = "/usr/local/bin/ynh-vpnclient restart"
+    print("Critical part: reloading vpnclient using '%s'" % restart_command)
     try:
-        subprocess.check_output("/usr/local/bin/ynh-vpnclient restart".split())
+        subprocess.check_output(restart_command.split())
     except Exception:
         # print("ERROR: command failed, displaying logs")
         # print("\n".join(open("/var/log/openvpn.log", "r").split("\n")[-200:]))