title: Error when using vuex-module-decorators and @nuxtjs/auth together
body: <p>I am using nuxtjs with typescript and use vuex-module-decorators. but I get error when add <code>@nuxtjs/auth</code> to my project.</p>
  <blockquote>
  <p>Uncaught (in promise) Error: ERR_STORE_NOT_PROVIDED: To use
  getModule(), either the module
  should be decorated with store in decorator, i.e. @Module({store: store}) or
  store should be passed when calling getModule(), i.e. getModule(MyModule, this.$store)</p>
  </blockquote>
  <p>This error happen when call Action.</p>
  <p>When <code>@nuxtjs/auth</code> from modules it's ok.</p>
  <p><em>store/index.ts</em></p>
  <pre><code>import { Store } from &quot;vuex&quot;;
  import { initializeStores } from &quot;~/utils/store-accessor&quot;;
  const initializer = (store: Store&lt;any&gt;) =&gt; initializeStores(store);
  export const plugins = [initializer];
  export * from &quot;~/utils/store-accessor&quot;;
  </code></pre>
  <p><em>utils/store-accessor</em></p>
  <pre><code>/* eslint-disable import/no-mutable-exports */
  import { Store } from &quot;vuex&quot;;
  import { getModule } from &quot;vuex-module-decorators&quot;;
  import { NuxtAxiosInstance } from &quot;@nuxtjs/axios&quot;;
  import Login from &quot;~/store/Login&quot;;
  import App from &quot;~/store/App&quot;;
  
  let $axios: NuxtAxiosInstance;
  
  function initializeAxios(axiosInstance: NuxtAxiosInstance) {
      $axios = axiosInstance;
  }
  
  let loginStore: Login, appStore: App;
  
  function initializeStores(store: Store&lt;any&gt;): void {
      loginStore = getModule(Login, store);
      appStore = getModule(App, store);
  }
  
  export { initializeStores, initializeAxios, loginStore, appStore, $axios };
  </code></pre>