invalid Toolchain. Your app was built with an unsupported version of Xcode or SDK

解决方案：

下载/更新 Xcode 11.2.1 （https://developer.apple.com/download/）

错误提示：

ERROR ITMS-90534: "Invalid Toolchain. Your app was built with an unsupported version of Xcode or SDK. If you plan to submit this build to the App Store, make sure you are using the GM version of Xcode 10.1 and the SDK for iOS 12.1 and watchOS 5.1, Xcode 7.1 and the SDK for tvOS 9, or Xcode 6 and the SDK for macOS 10.9 or later. If you are using an Xcode beta version to test your app, make sure you are using the latest supported version. For more information about supported beta versions, view the App Store Connect What's New page (https://developer.apple.com/app-store-connect/whats-new/)."

WARNING ITMS-90703: "Deprecated Xcode Build. Due to resolved app archives issues, we have deprecated Xcode 11.2 on November 5, 2019. Download Xcode 11.2.1 or newer, rebuild your app and resubmit."