ci(release-action): fix generate artifact attestation step

Author: lukewhrit

.github/workflows/release.yml

@@ -50,6 +50,6 @@ jobs:
       - name: Generate artifact attestation
         uses: actions/attest-build-provenance@v1
         with:
-          subject-name: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME}}
+          subject-name: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
           subject-digest: ${{ steps.push.outputs.digest }}
           push-to-registry: true