Remove not-all-data-replicated section

What does this MR do?

This MR removes the section titled "Not all data is replicated". The section points to a chart where all data-types are now being replicated. It mentions the container registry but going to the container registry sync section has entirely different instructions. The instructions seem to be unrelated. The chart shows the container registry is being sync'd anyway, so this section doesn't seem applicable any more.

Since all items have been migrated to the self-service framework, this no longer seems applicable. "Not all data is replicated" should be considered a bug now.

Related issues

MR raised as a customer ticket pointed out the discrepancy. (ZD internal: https://gitlab.zendesk.com/agent/tickets/496706)

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