add modules test

The build of package 'nodeinfo' is implicitly tested by the modules test.

test/test.nix

@@ -0,0 +1,52 @@
+# Integration test, can be run without internet access.
+
+import ./make-test.nix rec {
+  name = "nix-bitcoin";
+
+  hardened = {
+    imports = [ <nixpkgs/nixos/modules/profiles/hardened.nix> ];
+    security.allowUserNamespaces = true; # reenable disabled option
+  };
+
+  machine = { pkgs, lib, ... }: with lib; {
+    imports = [
+      ../modules/nix-bitcoin.nix
+      ../modules/secrets/generate-secrets.nix
+      # using the hardened profile increases total test duration by ~50%, so disable it for now
+      # hardened
+    ];
+
+    services.nix-bitcoin.enable = true;
+    services.bitcoind.extraConfig = mkForce "connect=0";
+
+    services.clightning.enable = true;
+    services.spark-wallet.enable = true;
+    services.lightning-charge.enable = true;
+    services.nanopos.enable = true;
+
+    services.lnd.enable = true;
+    systemd.services.lnd.wantedBy = mkForce [];
+
+    services.electrs.enable = true;
+
+    services.liquidd = {
+      enable = true;
+      listen = mkForce false;
+      extraConfig = "noconnect=1";
+    };
+
+    services.nix-bitcoin-webindex.enable = true;
+
+    services.hardware-wallets = {
+      trezor = true;
+      ledger = true;
+    };
+
+    # to test that unused secrets are made inaccessible by 'setup-secrets'
+    systemd.services.generate-secrets.postStart = ''
+      install -o nobody -g nogroup -m777 <(:) /secrets/dummy
+    '';
+  };
+
+  testScript = builtins.readFile ./test-script.py;
+}