Add a label when a public API changes (#4946)
Add a label when a public API changes (#4946)

This can then be used in conjunction with eventually adding comments with diffs, etc.
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