Add information if execution timed out during scoring

app/controllers/concerns/submission_scoring.rb

@@ -56,6 +56,10 @@ module SubmissionScoring
         unless output.nil?
           score += output[:score] * output[:weight]
         end
+
+        if output[:status] == :timeout
+          output[:stderr] += "\n\n#{t('exercises.editor.timeout', permitted_execution_time: submission.exercise.execution_environment.permitted_execution_time.to_s)}"
+        end
       end
     end
     submission.update(score: score)