nixos/mediatomb: wait for network-online.target

nixos/modules/services/misc/mediatomb.nix

···
     in mkIf cfg.enable {
     systemd.services.mediatomb = {
       description = "${cfg.serverName} media Server";
-      after = [ "network.target" ];
+      # Gerbera might fail if the network interface is not available on startup
+      # https://github.com/gerbera/gerbera/issues/1324
+      after = [ "network.target" "network-online.target" ];
       wantedBy = [ "multi-user.target" ];
       serviceConfig.ExecStart = "${binaryCommand} --port ${toString cfg.port} ${interfaceFlag} ${configFlag} --home ${cfg.dataDir}";
       serviceConfig.User = cfg.user;