message: fix(sdk): Remove event listeners on unsubscribe
  Change-Type: patch
diff: @@ -180,7 +180,6 @@ SDK.Scanner = class Scanner extends EventEmitter {
  }
  this.adapters.forEach((adapter) => {
  - // Adapter.stopScan()
  adapter.removeListener('devices', this.onDevices)
  adapter.removeListener('error', this.onError)
  })
  @@ -231,6 +230,9 @@ SDK.Scanner = class Scanner extends EventEmitter {
  return this
  }
  + instance.removeListener('devices', this.onDevices)
  + instance.removeListener('error', this.onError)
  +
  this.adapters.delete(instance.name)
  this.emit('unsubscribe', adapter)
  