public abstract RegularFileProperty getReportFile();

    @TaskAction
    public void checkDeadLinks() {
        Map<File, List<Error>> errors = new TreeMap<>();

        getDocumentationRoot().getAsFileTree().matching(pattern -> pattern.include("**/*.adoc")).forEach(file -> {
            gatherDeadLinksInFile(file, errors);
        });
        reportErrors(errors, getReportFile().get().getAsFile());
    }

        TaskProvider<FindBrokenInternalLinks> checkDeadInternalLinks = tasks.register("checkDeadInternalLinks", FindBrokenInternalLinks.class, task -> {
            task.getReportFile().convention(layout.getBuildDirectory().file("reports/dead-internal-links.txt"));
            task.getDocumentationRoot().convention(extension.getUserManual().getStagedDocumentation());