Update config.js

Avoids hard coded wireguard port when setting the ip tables port value but instead utilizes the configuration value.

src/config.js

@@ -20,7 +20,7 @@ module.exports.WG_ALLOWED_IPS = process.env.WG_ALLOWED_IPS || '0.0.0.0/0, ::/0';
 module.exports.WG_PRE_UP = process.env.WG_PRE_UP || '';
 module.exports.WG_POST_UP = process.env.WG_POST_UP || `
 iptables -t nat -A POSTROUTING -s ${module.exports.WG_DEFAULT_ADDRESS.replace('x', '0')}/24 -o ${module.exports.WG_DEVICE} -j MASQUERADE;
-iptables -A INPUT -p udp -m udp --dport 51820 -j ACCEPT;
+iptables -A INPUT -p udp -m udp --dport ${module.exports.WG_PORT} -j ACCEPT;
 iptables -A FORWARD -i wg0 -j ACCEPT;
 iptables -A FORWARD -o wg0 -j ACCEPT;
 `.split('\n').join(' ');