[fix] Let VPN mount

conf/ynh-vpnclient

@@ -129,6 +129,10 @@ start_openvpn() {
     [ "${ynh_server_proto}" == tcp ] && proto=tcp-client
   fi
 
+  # Unset firewall to let DNS and NTP resolution works
+  # Firewall is reset after vpn is mounted (more details on #1016)
+  unset_firewall
+  
   sync_time
 
   cp /etc/openvpn/client.conf{.tpl,}