Operator: Note on 2.0.x operator upgrade page needs reordering

Page : https://docs.couchbase.com/operator/2.0/howto-operator-upgrade.html#update-resources

Problem Statement:

Under operator upgrade page, Section 4 - Update the Resources, there is note about installing admission controller before any CouchbaseCluster resource is upgraded.

You can safely install the Dynamic Admission Controller — on its own — before running this update step. This will provide additional safety by validating updated and new resources for correctness. Separate installation instructions are documented for Kubernetes and OpenShift.

That note, being at the end of the section is often missed by the user due to the tendency of copying the steps in the flow as mentioned in the docs. By the time user reads that note its already too late as cbopconv has already converted the CouchbaseCluster resource without getting validated by DAC (because there isn't any DAC running at that time).

It would be best to push that Note right at the very beginning of this step.