Description of problem:{}

CI jobs for the RHDH Operator on OSD clusters started failing with the following error when attempting to create an ImageContentSourcePolicy (ICSP):

admission webhook "imagecontentpolicies-validation.managed.openshift.io" denied the request: Managed OpenShift customers may not create ImageContentSourcePolicy, ImageDigestMirrorSet, or ImageTagMirrorSet resources that configure mirrors that would conflict with system registries (e.g. quay.io, registry.redhat.io, registry.access.redhat.com, etc).
 

Prerequisites (if any, like setup, operators/versions):

Steps to Reproduce:

1. Trigger the nightly operator job on an OSD GCP cluster (e.g., release-1.6).

1. Observe the failure during ICSP creation from the install-rhdh-catalog-source.sh script.

Actual results: The install script fails due to a forbidden ICSP source, causing the job to error out.

Expected results: ICSP creation should not fail for valid mirror configurations

Reproducibility (Always/Intermittent/Only Once):

Build Details:

Additional info (Such as Logs, Screenshots, etc):

https://redhat-internal.slack.com/archives/C07D05S8U82/p1745395510212189