Add docker image sanity tests (#486)

Author: DannyBen

.github/workflows/test.yml

@@ -118,3 +118,18 @@ jobs:
 
     - name: Run schema tests
       run: bundle exec run schema all
+
+  docker:
+    name: Docker smoke test
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Checkout code
+      uses: actions/checkout@v3
+
+    - name: Build the image
+      run: docker compose build bash
+
+    - name: Test pandoc presence
+      run: docker compose run pandoc-test

docker-compose.yml

@@ -0,0 +1,18 @@
+services:
+  bash:
+    build: .
+    <<: &default
+      entrypoint: []
+      image: dannyben/bashly
+
+  bashly:
+    build: .
+    image: dannyben/bashly
+
+  bashly-test:
+    <<: *default
+    command: bashly --version
+
+  pandoc-test:
+    <<: *default
+    command: pandoc --version