add another matrix dimension to container hooks (#281)

.github/workflows/arc2-container-test.yml

@@ -9,29 +9,19 @@ on:
         required: true
 
 jobs:
-  hello-world-alpine:
+  hello-world:
     runs-on: ${{ github.event.inputs.target-scale-set }}
-    container: "alpine:3"
     strategy:
-      matrix: # A matrix of 4 is probably quite plenty
+      matrix:
         number: [1, 2]
         letter: [a, b]
+        base-image:
+          ["alpine:3", "cgr.dev/chainguard/wolfi-base:latest", "ubuntu:latest"]
+    container: ${{ matrix.base-image }}
     steps:
       - name: Hello world
         run: |
-          echo "Hello world"
-          echo "Number: ${{ matrix.number }}"
-          echo "Letter: ${{ matrix.letter }}"
-  hello-world-wolfi:
-    runs-on: ${{ github.event.inputs.target-scale-set }}
-    container: "cgr.dev/chainguard/wolfi-base:latest"
-    strategy:
-      matrix: # A matrix of 4 is probably quite plenty
-        number: [1, 2]
-        letter: [a, b]
-    steps:
-      - name: Hello world
-        run: |
-          echo "Hello world"
+          echo "Hello world - I'm running on ${{ runner.os }}!"
           echo "Number: ${{ matrix.number }}"
           echo "Letter: ${{ matrix.letter }}"
+          echo "Base image: ${{ matrix.base-image }}"