title: How to run all tests with minitest?
body: <p>I downloaded source code for a project, found a bug, and fixed it.</p>
  
  <p>Now I want to run tests to find out if I have broken anything.</p>
  
  <p>The Tests are in minitest DSL.</p>
  
  <p>How do I run them all at once?</p>
  
  <p>I searched for applicable rake tasks etc, but I  didn't find any.</p>