maybe fix workflow

.github/workflows/test-import-using-nix.yml

@@ -15,6 +15,8 @@ jobs:
         with:
           fetch-depth: 0
       - uses: cachix/install-nix-action@v11
+        env:
+          ACTIONS_ALLOW_UNSECURE_COMMANDS: true
         with:
           nix_path: nixpkgs=https://github.com/NixOS/nixpkgs/archive/20.09.tar.gz
           install_url: https://github.com/numtide/nix-flakes-installer/releases/download/nix-3.0pre20201007_5257a25/install

.github/workflows/test.yml

@@ -0,0 +1,20 @@
+name: "Test"
+on:
+  pull_request:
+  push:
+jobs:
+  tests:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+      with:
+          # Nix Flakes doesn't work on shallow clones
+          fetch-depth: 0
+    - uses: cachix/install-nix-action@v11
+      env:
+        ACTIONS_ALLOW_UNSECURE_COMMANDS: true
+      with:
+        install_url: https://github.com/numtide/nix-flakes-installer/releases/download/nix-3.0pre20200820_4d77513/install
+        extra_nix_config: |
+          experimental-features = nix-command flakes
+    - run: nix-build