hetzner: Add new server config

configuration/hardware-specific/vm.nix

@@ -4,6 +4,7 @@
   # Disable graphical tty so -curses works
   boot.kernelParams = ["nomodeset"];
 
+  networking.hostName = "testvm";
   # Sets the base domain for nginx to localhost so that we
   # can easily test locally with the VM.
   services.nginx.domain = lib.mkOverride 99 "localhost";