feat(wpcarro/ava): Support virtualbox

This has been useful while developing my NixOS installer.

Change-Id: I45fd5e1647248a6ebf277ffff3638587d8cc695d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/5559
Reviewed-by: wpcarro <wpcarro@gmail.com>
Autosubmit: wpcarro <wpcarro@gmail.com>
Tested-by: BuildkiteCI

users/wpcarro/nixos/ava/default.nix

@@ -82,6 +82,7 @@ in
       wpcarro.keys.nathan
     ];
   };
+  users.extraGroups.vboxusers.members = [ "wpcarro" ];
 
   security.sudo.wheelNeedsPassword = false;
 
@@ -100,6 +101,7 @@ in
   programs = wpcarro.common.programs;
 
   virtualisation.docker.enable = true;
+  virtualisation.virtualbox.host.enable = true;
 
   environment.variables = {
     EDITOR = "emacsclient";