莫名其妙出现这个问题，推测是安装了Xcode iOSopendev模版导致，
打开terminal 执行sudo chmod -R 777 /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk
这是为了获得修改文件夹权限
进入 /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS.sdk/SDKSettings.plist
修改CODE_SIGNING_REQUIRED字段为YES
重启xcode