title: running test command using lerna managed monorepo using --scope fails
body: <p>I'm using <code>lerna</code> to manage my monorepo, for some reason, when I try to run the following command from the root folder (<a href="https://github.com/lerna/lerna/tree/master/commands/run#readme" rel="nofollow noreferrer">using the docs here</a>): <code>lerna run --scope my-app test</code> I get the following error of lerna didn't find the module to run <code>npm test</code> on:</p>
  
  <pre class="lang-sh prettyprint-override"><code>lerna notice cli v3.20.2
  lerna info versioning independent
  lerna notice filter including "my-app"
  lerna info filter [ 'my-app' ]
  lerna ERR! EFILTER No packages remain after filtering [ 'my-app' ]
  </code></pre>
  
  <p>My <code>lerna.json</code> file has this definitions:</p>
  
  <pre><code>"packages": [
      "app1",
      "some-package-with-my-app/*",
      "app2",
      "app3"
    ],
  </code></pre>
  
  <p>I also tried to run <code>lerna run --scope some-package-with-my-app/my-app test</code> but got the same error (with the corresponding filter name, of course)</p>
  
  <p>What am I doing wrong? Am I missing something in the <a href="https://github.com/lerna/lerna/tree/master/commands/run#readme" rel="nofollow noreferrer">docs</a>?</p>