Attestations for
  ghcr.io/boks-sh/ruby@sha256:33fb679150c361c3d517164bad971ac00f4c3e89db2d2f36d8b46e9523fbe23a

Verify them yourself:
  cosign verify-attestation --key cosign.pub \
      --type <cyclonedx|slsaprovenance> ghcr.io/boks-sh/ruby@sha256:33fb679150c361c3d517164bad971ac00f4c3e89db2d2f36d8b46e9523fbe23a

=== cyclonedx ===================================================
  (no attestation matches the document published now -- 0 older one(s) are attached)

=== slsaprovenance ==============================================
  (no attestation matches the document published now -- 0 older one(s) are attached)