Revert "Update WatchKit App's Device Family setting"

Because if apply this commit, Watch app does not work on iOS simulator with "rake watch"

Author: Creative Ideas For Instagram Posts

lib/motion/project/template/ios-watch-extension-config.rb

@@ -170,7 +170,7 @@ def identifier
  #
  def merged_info_plist(platform)
  plist = super
- plist['UIDeviceFamily'] = [4] # Probably means Apple Watch device?
+ plist['UIDeviceFamily'] << 4 # Probably means Apple Watch device?
  plist['WKWatchKitApp'] = true
  plist['WKCompanionAppBundleIdentifier'] = ENV['RM_TARGET_HOST_APP_IDENTIFIER']
  plist.delete('UIBackgroundModes')