Introduce an axon-example

[lfgcampos]

Enhancement Description

Following the pattern we have on other extensions (kotlin, mongo, kafka, tracing, etc), we should introduce an amqp-axon-example on this repo where it serves to showcase how to use the extension but also for testing purposes when updating it.

Current Behaviour

There is no example project.

Wanted Behaviour

N/A

Possible Workarounds

N/A