remove pkgs.python3.future

the future python library doesn't exist in current nixpkgs version for
python3.13. removing this allows us to compile without overriding
nixpkgs version

Author: mazunki

default.nix

@@ -13,7 +13,6 @@ pkgs.python3.pkgs.buildPythonPackage rec {
   ];
 
   dependencies = with pkgs.python3.pkgs; [
-    future
     jsonschema
     psutil
   ];

pyproject.toml

@@ -10,7 +10,6 @@ name = "vmrunner"
 version = "0.16.0"
 description = "A qemu convenience wrapper for writing integration tests"
 dependencies = [
-    "future",
     "jsonschema",
     "psutil",
 ]