docs(firestore): formatting (#6630)
docs(firestore): formatting (#6630)

* docs(firestore): formatting

* docs(firestore): tweak merge docs

* docs(firestore): correct formatting
firebase/flutterfire,firebase/flutterfire,firebase/flutterfire,firebase/flutterfire,firebase/flutterfire,firebase/flutterfire,firebase/flutterfire,firebase/flutterfire,firebase/flutterfire,firebase/flutterfire