chore: Add CI tests

.github/workflows/test.yml

@@ -0,0 +1,21 @@
+name: Test
+
+on:
+  push:
+    paths:
+    - '**/*.nix'
+
+jobs:
+  check:
+    runs-on: ubuntu-latest
+    steps:
+    steps:
+    - uses: actions/checkout@v2.4.0
+    - uses: cachix/install-nix-action@v16
+      with:
+        install_url: https://nixos-nix-install-tests.cachix.org/serve/vij683ly7sl95nnhb67bdjjfabclr85m/install
+        install_options: '--tarball-url-prefix https://nixos-nix-install-tests.cachix.org/serve'
+        extra_nix_config: |
+          access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}
+    - name: Run tests
+      run: nix-instantiate --eval --strict test/test.nix