Story: As a user of the mirror registry for OpenShift, I want to be able to store Helm charts in OCI format

Background: An increase in requests for Helm chart support in OMR is currently seen from customers and partners who rely on the mirror registry to stand up a disconnected OCP cluster which is then customized using Helm charts. These typically contain CSI or CNI drivers which are not part of our official operator catalogs.

Acceptance criteria:

• I can push Helm OCI charts to OMR
• the Helm OCI media type is enabled by default in OMR
• the Helm OCI media type is enabled by default after an update of OMR