Bump github.com/opencontainers/image-spec from 1.1.0-rc3 to 1.1.0-rc.6

Bumps [github.com/opencontainers/image-spec](https://github.com/opencontainers/image-spec) from 1.1.0-rc3 to 1.1.0-rc.6.
- [Release notes](https://github.com/opencontainers/image-spec/releases)
- [Changelog](https://github.com/opencontainers/image-spec/blob/main/RELEASES.md)
- [Commits](opencontainers/image-spec@v1.1.0-rc3...v1.1.0-rc6)

---
updated-dependencies:
- dependency-name: github.com/opencontainers/image-spec
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

go.mod

@@ -9,7 +9,7 @@ require (
  github.com/containerd/containerd v1.6.19
  github.com/go-git/go-git/v5 v5.11.0
  github.com/google/go-cmp v0.6.0
- github.com/google/go-containerregistry v0.18.0
+ github.com/google/go-containerregistry v0.17.0
  github.com/google/uuid v1.6.0
  github.com/hashicorp/errwrap v1.1.0 // indirect
  github.com/hashicorp/go-multierror v1.1.1
@@ -50,8 +50,8 @@ require (
  code.gitea.io/sdk/gitea v0.17.1
  github.com/goccy/kpoward v0.1.0
  github.com/google/cel-go v0.19.0
- github.com/google/go-containerregistry/pkg/authn/k8schain v0.0.0-20240108195214-a0658aa1d0cc
- github.com/google/go-containerregistry/pkg/authn/kubernetes v0.0.0-20240108195214-a0658aa1d0cc
+ github.com/google/go-containerregistry/pkg/authn/k8schain v0.0.0-20240129192428-8dadbe76ff8c
+ github.com/google/go-containerregistry/pkg/authn/kubernetes v0.0.0-20240129192428-8dadbe76ff8c
  github.com/sigstore/sigstore/pkg/signature/kms/aws v1.8.1
  github.com/sigstore/sigstore/pkg/signature/kms/azure v1.8.1
  github.com/sigstore/sigstore/pkg/signature/kms/gcp v1.8.1