Fix root attribute in GitHub action.

.github/actions/nix-ros-build-action/dist/index.js

@@ -1141,9 +1141,9 @@ function run() {
             const parallelism = core.getInput('parallelism');
             const cachixCache = core.getInput('cachix-cache');
             const cachixSigningKey = core.getInput('cachix-signing-key');
-            //await cachix.install(nixpkgs)
+            yield cachix.install(nixpkgs);
             core.startGroup(`Setting up Cachix cache: ${cachixCache}`);
-            //await cachix.use(cachixCache)
+            yield cachix.use(cachixCache);
             if (cachixSigningKey !== "") {
                 core.exportVariable('CACHIX_SIGNING_KEY', cachixSigningKey);
             }

.github/workflows/build.yaml

@@ -2,11 +2,17 @@ name: "Build"
 on:
   push:
 jobs:
-  tests:
+  build:
     runs-on: ubuntu-latest
+    strategy:
+    matrix:
+      distro:
+        - melodic
+        - dashing
     steps:
     - uses: actions/checkout@v1
     - uses: cachix/install-nix-action@v6
     - uses: ./.github/actions/nix-ros-build-action
       with:
+        root-attribute: '${{ matrix.distro }}'
         cachix-signing-key: '${{ secrets.CACHIX_SIGNING_KEY }}'