Document how to migrate from existing self-hosted K8s deployment to using the Operator with no downtime

[johnrk-zz]

Exalate commented:

Towards this issue of enabling seamless migrations from self-hosted K8s deployments using the Helm Chart or Statefulsets using the Operator, we should document that process. More details on how users will do that is to be determined.

This is not part of the K8s Operator MVP.

Jira Issue: DOC-646

[github-actions]

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[adamzr]

This is still an issue. We would like to migrate to the operator, but no upgrade path is documented.

[lucacri]

Same here, any updates?