title: AWS Amplify Auth.sendCustomChallengeAnswer issue
body: <p>I'm using a Custom-Challenge Authentication with AWS Amplify, Cognito, and React Native, implementing a Passwordless authentication process. The App was working ok, but for some reason after added a couple of new libraries just the authentication part stopped to work.</p>
  <p>When I try to run this part:</p>
  <pre><code> import {Auth} from 'aws-amplify';
   const user = await Auth.signIn(username); // This part its OK
   const signedUser = await Auth.sendCustomChallengeAnswer(user, confirmationCode); // This one breaks
  </code></pre>
  <p>The message I receive is this:
  <code>TypeError: (0, _getRandomBase.default) is not a function</code></p>
  <p>A bit of more information about the project:</p>
  <ul>
  <li>&quot;aws-amplify&quot;: &quot;3.0.21&quot;,</li>
  <li>&quot;aws-amplify-react-native&quot;: &quot;4.2.2&quot;,</li>
  <li>&quot;amazon-cognito-identity-js&quot;: &quot;4.3.3&quot;,</li>
  <li>&quot;@react-native-community/netinfo&quot;: &quot;5.9.5&quot;,</li>
  </ul>
  <p>My index.js file:</p>
  <pre><code>import Amplify from 'aws-amplify';
  Amplify.configure({
    Auth: {...},
    API: {...},
    PushNotification: {...},
  })
  </code></pre>
  <p>In Cognito I setup all the necessary Triggers like:</p>
  <ul>
  <li>CreateAuthChallenge, =&gt; This one is reached</li>
  <li>DefineAuthChallenge, =&gt; This one as well</li>
  <li>VerifyAuthChallenge, =&gt; This one is never reached!!!</li>
  </ul>