SBOM tab should not exist when the artifact is oci-compliant helm-chart

[Shengwen YU]

How to reproduce?

1. git clone -b 1.14.0 https://github.com/goharbor/harbor-helm.git
2. mkdir temp && cd temp && helm package ../harbor-helm
3. you will see there is a chart file, such as harbor-1.14.2.tgz being generated
4. deploy Harbor with the latest build
5. navigate to harbor portal and create a project named as oci-charts
6. helm login registry <harbor-endpoint>
7. helm push harbor-1.14.2.tgz oci://<harbor-endpoint>/oci-charts
8. the oci-compliant chart will be uploaded to harbor, but the SBOM tab should NOT be there