title: Hide packages inside my flutter app in LicensePage
body: <p>I'm using the build in LicensePage class to show all my dependencies licenses.</p>
  <p>But it also shows the sub packages inside of my app folder. Is there a way to hide them in the list?</p>
  <p>I tried to set <code>publish_to: none</code> in each pubspec.yml file from the packages .. but it doesn't work.</p>
  <p>The LicenseRegistry has a addLicense method. But there is no removeLicense or something else.</p>
  <p>Is there any way to hide packages inside my app from the LicensePage overview?</p>