title: How to get access token of auth0 in Vue app just mounted
body: <p>I can get access token in methods.
  But, I can't get access token in mounted() and created().</p>
  
  <p><a href="https://auth0.com/docs/quickstart/spa/vuejs/01-login" rel="nofollow noreferrer">https://auth0.com/docs/quickstart/spa/vuejs/01-login</a></p>
  
  <p>i added for quickstart sample in <code>this.accessToken = await this.auth0Client.getTokenSilently();</code></p>
  
  <p>app.js</p>
  
  <pre><code>...
  
  // Import the Auth0 configuration
  import { domain, clientId, audience } from "./auth/auth_config.json";
  
  // Import the plugin here
  import { Auth0Plugin } from "./auth";
  
  // Install the authentication plugin here
  Vue.use(Auth0Plugin, {
    domain,
    clientId,
    audience,
    onRedirectCallback: appState =&gt; {
      router.push(
        appState &amp;&amp; appState.targetUrl
          ? appState.targetUrl
          : window.location.pathname
      );
    }
  });
  
  ...
  </code></pre>
  
  <p>test.vue</p>
  
  <pre><code>&lt;template&gt;
    &lt;div&gt;
      Auth0 Email: {{ $auth.user.email }}
      Auth0 AccessToken: {{ tokenOutput() }}
    &lt;/div&gt;
  &lt;/template&gt;
  
  &lt;script&gt;
    export default {
      async created() {
        console.log(await this.$auth.accessToken); // null
      },
      async mounted() {
        console.log(await this.$auth.accessToken); // null
      },
      methods: {
        tokenOutput: function(){
          return this.$auth.accessToken;
        }
      }
    }
  &lt;/script&gt;
  </code></pre>
  
  <p><code>$auth.user.email</code> and <code>tokenOutput()</code> is output.
  but, <code>this.$auth.accessToken</code> is null.
  can i get access token of auth0 in Vue app just mounted.</p>
  
  <p>Thanks.</p>