Add Hibernate Reactive extension (beta)

[aguibert]

Describe the extension
Currently there is ongoing work in HibernateRX to offer a reactive form of Hibernate ORM. Since both Hibernate and reactive technologies exist in Quarkus today, it would make sense to have an extension that combines the two.

Interested in this extension, please +1 via the emoji/reaction feature of GitHub (top right).

Configuration suggestion
Same configuration as Hibernate ORM (non-reactive). Currently HibernateRX standalone can be configured with a JDBC URL, but in addition to that Quarkus also supports more generic datasource configuration.

Additional context
Suggested extension name: hibernate-rx (HibernateRX is a working title, and as the underlying project changes the extension name may change to reflect that)

CC @Sanne @gavinking

[quarkusbot]

/cc @gsmet @Sanne

[aguibert]

I plan on working on this issue so please assign to me

[Sanne]

This was fixed by #9060 - which is now merged.