🧪 Experiment with new attestation action

This attempts to enable attestation on the output artifacts from the
`bundle` workflow.

.github/workflows/bundle.yaml

@@ -81,6 +81,13 @@ jobs:
           profile: ${{ steps.select.outputs.profile }}
           path: ${{ matrix.renderer }}-example
 
+      - name: Attest Provenance
+        id: provenance
+        uses: actions/attest-build-provenance@v1
+        with:
+          subject-name: ${{ inputs.artifact-prefix }}${{ steps.bundle.outputs.artifact_name }}
+          subject-path: ${{ steps.bundle.outputs.artifact_path }}
+
       - name: Upload Bundle Artifact
         id: upload
         uses: actions/upload-artifact@v4