Explore usage of xref usage for downstream docs

In DBZ-4776 we clarified the current requirements for links in the Debezium documentation. Due to limitations in downstream tooling, we currently cannot use the "xref" macro for any inter-page links, which results in a sub-optimal editing experience. Let's investigate time-boxed to 1d max, why that is, and whether we can overcome this. Ideally, we'd use the xref syntax without any variables for prefix or page names consistently, everywhere.