Add a link to the WildFly Quickstarts repository on the WildFly documentation

On the WildFly documentation index (e.g https://docs.wildfly.org/23/), we have an entry point for the Quickstarts with a very short description, however, there is no direct link to point out to the user the WildFly Quickstart repository. The repository contains a readme that gives more information about the Quickstart, so, at least, give it this link from the WildFly documentation.