fix typo

flake.nix

@@ -36,7 +36,7 @@
     nixosConfigurations = let
       make-nixos-system = host: let
         hyper = get-hyper host;
-        rice = get-rice hyeper;
+        rice = get-rice hyper;
       in nixpkgs.lib.nixosSystem { 
         pkgs = get-pkgs hyper;
         modules = [ ./configuration.nix ];