Improves detection of WP Version, Plugins etc by checking 404

spec/app/finders/themes/urls_in_404_page_spec.rb

@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+describe WPScan::Finders::Themes::UrlsIn404Page do
+  subject(:finder) { described_class.new(target) }
+  let(:target)     { WPScan::Target.new(url) }
+  let(:url)        { 'http://wp.lab/' }
+  let(:fixtures)   { FINDERS_FIXTURES.join('themes', 'urls_in_404_page') }
+
+  # This stuff is just a child class of URLsInHomepage (using the error_404_res rather than homepage_res)
+  # which already has a spec
+end