argunix pre-flight: no connected builder satisfies this derivation's
requiredSystemFeatures. Failing fast instead of waiting for nix's
remote-build scheduler to give up.

attribute: packages.x86_64-linux.test-extensions
derivation: /nix/store/az1nv9021b59cvmck10jjd9yv1pdgyj6-vm-test-run-talos-clone-extensions.drv
required (system, features): (x86_64-linux, ["kvm", "nixos-test"])

connected builders: (none)

Fix one of:
  1. Add the missing feature(s) to a builder's nix.settings.system-features.
  2. Add a builder host that natively satisfies the feature.
  3. Drop the requirement from the derivation if it isn't actually needed.