gistfile1.txt

 networking.dhcpcd.enable = false;
  networking.useDHCP = false;
  networking.bridges.br0.interfaces = ["eno1"];
  networking.interfaces.br0.ipv4.addresses = [ { address = "62.xxx.xxx.xxx"; prefixLength = 24; } ];
  networking.defaultGateway = { address = "62.210.75.1"; interface = "br0"; };

  containers.test = {
    autoStart = true;
    privateNetwork = true;
    hostBridge = "br0";
    localAddress = "212.xxx.xxx.xxx"; # ipfo
    
    config = { config, pkgs, ... }: {
      networking.firewall.allowedTCPPorts = [ 80 443 22 ];
      networking.firewall.allowPing = true;

      services.openssh.enable = true;
      services.nginx = {
        enable = true;
      };
    };
  };

also try:

  containers.gitlab = {
    autoStart = true;
    privateNetwork = true;
    hostBridge = "br0";
    config = { config, pkgs, ... }: {
      networking.firewall.allowedTCPPorts = [ 80 22 ];
      networking.firewall.allowPing = true;
      networking.interfaces.eth0.ipv4.addresses = [{address = "212.xxx.xxx.xxx"; prefixLength = 32;}];
      networking.interfaces.eth0.macAddress = "xx:xx:00:00:xx:xx";
      networking.defaultGateway = { address = "62.210.0.1"; interface = "eth0"; };

      services.openssh.enable = true;
      services.nginx = { ...