Fix CKV_OCI_21

[tsmithv11]

Please always provide the GitHub issue(s) your PR is for, as well as test URLs where your change can be observed (before and after):

Fix https://github.com/bridgecrewio/checkov/issues/6745

Test URLs:

• Before: https://main--prisma-cloud-docs--hlxsites.hlx.page/
• After: https://--prisma-cloud-docs--hlxsites.hlx.page/
• Worker: https://prisma-cloud-docs-production.adobeaem.workers.dev/?branch=

[JBakstPaloAlto]

Merge as per @tsmithv11's request of 4 Nov 2024.