Add doc about Operator and CRD scope

[camilamacedo86]

trafficstars

What do you want to happen?

Context and Motivation

The Kubebuilder docs does not explain the Operator and CRD scope. Therefore, we have questions like https://github.com/kubernetes-sigs/kubebuilder/discussions/3155

The goal of the task

The goal of this task is to create those documentations under reference. See that is well documented in the Operator-SDK documentation:

• Operator Scope: https://sdk.operatorframework.io/docs/building-operators/golang/operator-scope/
• CRD scope: https://sdk.operatorframework.io/docs/building-operators/golang/crds-scope/

We can use the content available there to create a documentation in Kubebulder but we should not link Operator-SDK docs.

How to do it:

• Create a PR to add the doc under the section reference
• Update either the summury
• Verify your changes using the doc preview available when you push the PR

Extra Labels

/kind documentation