text: Title: Add option to keep hidden tests hidden during feedback step
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  ### Expected behavior
  
  I would expect that the system to keep hiding the hidden tests in the feedback students receive.
  
  ### Actual behavior
  
  The system reveals the hidden tests in the generated HTML file. Is this a bug, or is this actually on purpose?
  
  ### Steps to reproduce the behavior
  
  Feedback on a student's assignment wich has hidden tests.