Explicitly add `functions.ignore` options to firebase.json (#4838)
Explicitly add `functions.ignore` options to firebase.json (#4838)

We are hoping that this will improve discoverability of the `ignore` field while we think through how we want to document different firebase.json options for the functions project.
firebase/firebase-tools,firebase/firebase-tools,firebase/firebase-tools,firebase/firebase-tools,firebase/firebase-tools