todo title text update for manual todos

app/helpers/todos_helper.rb

@@ -12,6 +12,7 @@ module TodosHelper
     when Todo::ASSIGNED then 'assigned you'
     when Todo::MENTIONED then 'mentioned you on'
     when Todo::BUILD_FAILED then 'The build failed for your'
+    when Todo::MARKED then 'todo'
     end
   end