AnonymousAuthProvider signInOptions does not work; Throw a TypeError. #183

• Using AnonymousAuthProvider signInOptions does not work with react-firebaseui.
• It throws the following error: Uncaught TypeError: fn(...).signInAnonymously is not a function

Below is what my uiConfig looks like.

import { auth as firebaseuiAuth } from 'firebaseui';

const uiConfig = {
  signInFlow: 'popup',
  signInOptions: [
    firebaseuiAuth.AnonymousAuthProvider.PROVIDER_ID,
  ],
};