fixed bug about co-author-relation

spec/requests/desktop/co_authors_pages.spec.rb

@@ -3,4 +3,10 @@ require 'spec_helper'
 describe "Co-Author pages" do
   subject {co-author}
 
+  describe "Co-Author list" do
+    before { visit desktop_co_authors }
+
+    it { should have_selector('h1', text: 'Sign up') }
+  end
+
 end