title: Run a single test suite from build.sbt
body: <p>I have a multi-module project and currently run tests during packaging by a task which reads -</p>
  
  <pre><code>val testALL = taskKey[Unit]("Test ALL Modules")
  
  testALL := {
    (test in Test in module_A).value
    (test in Test in module_B).value
    (test in Test in module_C).value
  }
  </code></pre>
  
  <p>Now, I have consolidated all tests in each module into a single top-level ScalaTest Suite. So for each module want to only run this single top-level suite (named say "blah.moduleA.TestSuite" and so on). Have been trying to use testOnly and testFilter in my build.sbt to run just this single suite in each module but cant get the syntax right. Can someone please tell me how to do this?</p>