Use external repo for GoogleAppMeasurement SPM dependency (#7333)
Use external repo for GoogleAppMeasurement SPM dependency (#7333)

* Use external repo for GoogleAppMeasurement SPM dependency

* style

* review
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