Move Xcode 9.4 tests to cron since support won't be required next month (#2420)
Move Xcode 9.4 tests to cron since support won't be required next month (#2420)


firebase/firebase-ios-sdk,firebase/firebase-ios-sdk,firebase/firebase-ios-sdk,firebase/firebase-ios-sdk,firebase/firebase-ios-sdk,firebase/firebase-ios-sdk,firebase/firebase-ios-sdk