Fix Docker digest output reference in workflow

Updates the GitHub Actions workflow to use the correct step ID 'build-and-push' for the Docker image digest output, ensuring the provenance attestation references the correct value.

.github/workflows/docker.yml

@@ -53,6 +53,7 @@ jobs:
             type=raw,value=latest,enable={{is_default_branch}}
 
       - name: Build and push Docker image
+        id: build-and-push
         uses: docker/build-push-action@v5
         with:
           context: .
@@ -68,7 +69,7 @@ jobs:
         uses: actions/attest-build-provenance@v1
         with:
           subject-name: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME}}
-          subject-digest: ${{ steps.build.outputs.digest }}
+          subject-digest: ${{ steps.build-and-push.outputs.digest }}
           push-to-registry: true
 
   security-scan: