title: Change platform brigtness is triggered when 'Home' is pressed in iOS 15 Simulator
body: <p>I'm having an issue after my Simulator was updated to iOS 15 in my upcoming Flutter app. When I press the 'Home' button at the top it causes my app to fire the didChangePlatformBrightness() function twice.</p>
  <p>Seriously thinking on remove this check while the app is already open and leave it only at startup. Anyone with the same problem and any tips on how to solve it?</p>
  <p>On Android everything works fine, just as expected.</p>