Link from module doc to a list of how-tos

[tsegismont]

For some modules like Vert.x OpenTelemetry, it would be nice to have a link to a how-to.

Indeed, for such modules, usual examples (vertx-example) don't really make sense, because to demonstrate the feature many components are required (e.g. running a compatible tracing server in a container).

Perhaps there could be a link in the right side bar, or next to API Docs link (like examples).