Revert test changes

Author: hsubox76

config/firestore.rules

@@ -1,7 +1,7 @@
 service cloud.firestore {
   match /databases/{database}/documents {
     match /{document=**} {
-      allow read;
+      allow read, write;
     }
   }
 }

config/functions/index.js

@@ -19,8 +19,6 @@ const assert = require('assert');
 const cors = require('cors')({ origin: true });
 const functions = require('firebase-functions');
 
-// FIXME: test
-
 /*
  * These backend test helpers are copied from the iOS and Android SDKs, but are
  * not all implemented as tests in the JS SDK yet.