Fixing image signing on cosign

Signed-off-by: Jiri Podivin <jpodivin@redhat.com>

.github/workflows/docker-publish.yml

@@ -118,7 +118,22 @@ jobs:
         env:
           # https://docs.github.com/en/actions/security-guides/security-hardening-for-github-actions#using-an-intermediate-environment-variable
           TAGS: ${{ steps.meta.outputs.tags }}
-          DIGEST: ${{ steps.build-and-push.outputs.digest }}
+          DIGEST: ${{ steps.build-image.outputs.digest }}
+        # This step uses the identity token to provision an ephemeral certificate
+        # against the sigstore community Fulcio instance.
+        run: echo "${TAGS}" | xargs -I {} cosign sign --yes {}@${DIGEST}
+
+      # Sign the resulting Docker image digest except on PRs.
+      # This will only write to the public Rekor transparency log when the Docker
+      # repository is public to avoid leaking data.  If you would like to publish
+      # transparency data even for private images, pass --force to cosign below.
+      # https://github.com/sigstore/cosign
+      - name: Sign the published Docker image
+        if: ${{ github.event_name != 'pull_request' && contains(github.ref, 'refs/tags/') }}
+        env:
+          # https://docs.github.com/en/actions/security-guides/security-hardening-for-github-actions#using-an-intermediate-environment-variable
+          TAGS: ${{ steps.meta.outputs.tags }}
+          DIGEST: ${{ steps.build-image-cuda.outputs.digest }}
         # This step uses the identity token to provision an ephemeral certificate
         # against the sigstore community Fulcio instance.
         run: echo "${TAGS}" | xargs -I {} cosign sign --yes {}@${DIGEST}