Forgot to checkout and setup nix

Author: garbas

.github/workflows/nix.yml

@@ -15,6 +15,14 @@ jobs:
       packages: ${{ steps.packages.outputs.packages }}
 
     steps:
+    - name: Checkout
+      uses: actions/checkout@v3
+
+    - name: Setup
+      uses: ./.github/actions/nix-common-setup
+      with:
+        CACHIX_AUTH_TOKEN: ${{ secrets.CACHIX_AUTH_TOKEN }}
+
     - name: Packages
       id: packages
       run: |