fix(ios): call beginReceivingRemoteControlEvents

This ensures remote events are received.
It's a universal function for the audio session.
At least one audio app needs to call this, but
all of them should.

ios/MusicControlManager.m

@@ -229,6 +229,7 @@ - (void) toggleHandler:(MPRemoteCommand *) command withSelector:(SEL) selector e
 - (id)init {
     self = [super init];
     [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(audioHardwareRouteChanged:) name:AVAudioSessionRouteChangeNotification object:nil];
+    [[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
     self.audioInterruptionsObserved = false;
     return self;
 }