title: Flutter app works as .apk, but "installation failed" with firebase distribution
body: <p>I am trying to put a Flutter app on Firebase app distribution. I build the .apk, then transfer it onto my android phone. When I test it, no issues. Then, I upload the .apk to Firebase app distribution and try to install it on my phone (after deleting the first). The app downloads, and then attempts to install, but rather than finishing, it closes and gives the error: "Installation failed." I'm assuming this is an error with firebase distribution because the original .apk works, simply will not install when transferred onto distribution.</p>
  
  <p>Things I've tried:</p>
  
  <ul>
  <li>Enabling multidex</li>
  <li>Adding signing config</li>
  <li><code>flutter clean
  flutter build apk</code></li>
  </ul>
  
  <p>Any ideas? Thanks!</p>