register_task.kt

class BundleReleaseFilesPlugin : Plugin<Project> {

    override fun apply(target: Project) {
        ...
        val bundleReleaseFiles = target.tasks.register(
            "bundleReleaseFiles",
            BundleReleaseFilesTask::class.java
        ) {
            this.group = "my_plugins"
            this.description = "Bundle release files (APK, Bundle and mapping) in the same directory"
        }
    }
}