title: How can I avoid running some tests in parallel?
body: <p>I have a collection of tests. There are a few tests that need to access a shared resource (external library/API/hardware device). If any of these tests run in parallel, they fail.</p>
  
  <p>I know I could run everything using <code>--test-threads=1</code> but I find that inconvenient just for a couple of special tests.</p>
  
  <p>Is there any way to keep running all tests in parallel and have an exception for a few? Ideally, I would like to say do not run X, Y, Z at the same time.</p>