Generate SBOM/Attestations

Author: davidcollom

.github/workflows/build-test.yaml

@@ -114,6 +114,9 @@ jobs:
           tags: quay.io/jetstack/version-checker:${{github.sha}}
           cache-from: type=gha
           cache-to: type=gha,mode=max
+          sbom: true
+          attests: |-
+            type=sbom,generator=image
 
       - name: Run Trivy vulnerability scanner
         uses: aquasecurity/trivy-action@0.30.0