Ruby: remove a fixed TODO

Author: alexrford

ruby/ql/test/query-tests/security/cwe-079/app/views/foo/bars/show.html.erb

@@ -14,7 +14,7 @@
 <ul>
 <% for key in [:display_text, :safe_text] do %>
   <%# BAD: A local rendered raw via the locals hash %>
-  <%# TODO: we miss that `key` can take `:display_text` as a value here %>
+
   <li><%= raw local_assigns[key] %></li>
 <% end %>
 </ul>