Try to allow cross build

.gitea/workflows/check-flake.yaml

@@ -14,14 +14,12 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Install basic dependencies
-        run: apt-get update && apt-get install -y --no-install-recommends sudo curl ca-certificates xz-utils qemu-system-x86-64 qemu-efi binfmt-support qemu-user-static
+        run: apt-get update && apt-get install -y --no-install-recommends sudo curl ca-certificates xz-utils
 
       - name: Install Nix
         uses: https://github.com/cachix/install-nix-action@v20
         with:
           github_access_token: ${{ secrets.__GITHUB_TOKEN }}
-          extra_nix_config: |
-            system-features = nixos-test benchmark big-parallel kvm
 
       - name: Checkout the repository
         uses: actions/checkout@v3