ci: add Podman validation to the build-images step

Introduce a matrix in the Kubernetes integration tests job to support
both Docker and Podman for image builds. Add `oci_bin` as a matrix entry
to control which container runtime is used. Conditionally install Podman
when required and build images using the appropriate runtime.

Ensure that integration tests only run with Docker by skipping them when
Podman is used, avoiding unnecessary test runs. This change ensures
Podman compatibility for image builds while keeping the test process the
same for Docker.

Signed-off-by: Andrew McDermott <[email protected]>

.github/workflows/pull_request.yml

@@ -78,11 +78,12 @@ jobs:
         git diff --exit-code -I'^    createdAt: ' bundle
 
   kubernetes-integration-tests:
-    name: Kubernetes Integration Tests (Go ${{ matrix.go }} - amd64)
+    name: Kubernetes Integration Tests (Go ${{ matrix.go }} - amd64 - ${{ matrix.oci_bin }})
     runs-on: ubuntu-latest
     strategy:
       matrix:
         go: ['1.22']
+        oci_bin: ['docker', 'podman']
     env:
       BPFMAN_AGENT_IMG: quay.io/bpfman/bpfman-agent:int-test
       BPFMAN_OPERATOR_IMG: quay.io/bpfman/bpfman-operator:int-test
@@ -120,11 +121,19 @@ jobs:
         with:
           fetch-depth: 0
 
-      - name: Build Operator and Agent images
+      - name: Install OCI runtime (Docker or Podman)
         run: |
-          make build-images
+          if [ "${{ matrix.oci_bin }}" = "podman" ]; then
+            sudo apt-get update && sudo apt-get install -y podman
+          fi
 
+      - name: Build Operator and Agent images with ${{ matrix.oci_bin }}
+        run: |
+          make OCI_BIN=${{ matrix.oci_bin }} build-images
+
+      # Run integration tests only if OCI_BIN is Docker.
       - name: Run integration tests
+        if: ${{ matrix.oci_bin == 'docker' }}
         run: |
           make test-integration