Add a notation to express that a dependency should have the same version as the component

[jjohannes]

Sometimes, a dependency needs to be added that points another component of the same library. The dependency should then have the same version as the component itself if all components of the library share the same version.
In general, the component version is one of the few things that is known and accessible in a component metadata rule, but currently you cannot express that you would like to use it in our patch DSL.

For example, we could have something like this:

module("org.wiremock:wiremock") {
    addRuntimeOnlyDependency("org.wiremock:wiremock-jetty12", withComponentVersion = true)

    removeDependency("org.eclipse.jetty:jetty-server")
    // ...
}

Not sure what a good notation would be. The above is only a mockup.