Remove reference to Operator UI

[djwfyi]

Summary

The Configure MinIO to use KES page for OpenShift (and similar page for other platforms) retain references to use the no longer existing Operator UI for procedural steps.

We need to clean up additional references to the Operator UI on this and any other pages.

Goals

List the in-scope goals

• [ ] Provide instructions on the Configure MinIO and KES page that do not use the Operator UI
• [ ] Do a pass for other pages that may have lingering references to the Operator UI

[feorlen]

another straggler https://github.com/minio/docs/issues/1465