1. Proposed title of this feature request
Custom admin-acks for cluster upgrades

2. What is the nature and description of the request?
As a platform service provider we are providing our customers with OpenShift clusters. However, we do give away the entire cluster admin to them, thus they are fully responsible for their environments (besides some guard rails which we introduce for them for compliance reasons). As OpenShift is gating the platform upgrades with admin-acks, we are interested to introduce the same functionality for our internal rules / checks / update information. Basically we want to force the customers to read through our internal upgrade guideline each time and give their acknowledgement. Custom admin-acks would be great as it is already present in the upgrade workflow and we do not have to come up with something different (such as ValidatingAdmissionPolicies).

3. Why does the customer need this? (List the business requirements here)
To inform customers about important changes in the platform and / or environment related to the platform with upgrades

4. List any affected packages or components.
ClusterVersionOperator