fix: ensure restored devices stream completes on Android

This passes an empty restored device info collection to the restored
device event stream on Android to ensure the stream will emit a done
event.

packages/reactive_ble_mobile/android/src/main/kotlin/com/signify/hue/flutterreactiveble/channelhandlers/RestoredDeviceHandler.kt

@@ -1,6 +1,7 @@
 package com.signify.hue.flutterreactiveble.channelhandlers
 
 import io.flutter.plugin.common.EventChannel
+import com.signify.hue.flutterreactiveble.ProtobufModel as pb
 
 class RestoredDeviceHandler() : EventChannel.StreamHandler {
     private var sink: EventChannel.EventSink? = null
@@ -11,7 +12,11 @@ class RestoredDeviceHandler() : EventChannel.StreamHandler {
     ) {
         eventSink?.let {
             sink = eventSink
+
+            val message = pb.RestoredDeviceInfoCollection.newBuilder().build()
+            eventSink.success(message.toByteArray())
         }
+
     }
 
     override fun onCancel(objectSink: Any?) {