Xcode编译警告:warning: The iOS Simulator deployment target is set to 6.0, but the range of supported deployment target versions for this platform is 8.0 to 12.0. (in target 'Masonry')

问题原因：https://github.com/CocoaPods/CocoaPods/issues/8069

中文解决方案：https://www.jianshu.com/p/226832903157