For what is setting attributes on

Configuration#outgoing

? I was quickly under the impression this should control the attributes of the outgoing variant. But this is not the case.

configurations.apiElements {
    outgoing {
        attributes {
            attribute(GRADLE_PLUGIN_API_VERSION_ATTRIBUTE, objects.named("8.5"))
        }
    }
}

does not seem to do anything, but you have to do

configurations.apiElements {
    attributes {
        attribute(GRADLE_PLUGIN_API_VERSION_ATTRIBUTE, objects.named("8.5"))
    }
}