test: adds redux to main app story

This test failed until now to provide at storybook component as the redux store was not accessible.

apps/graphpolaris/src/app/app.stories.tsx

-import { Story, Meta } from '@storybook/react';
+import { configureStore } from '@reduxjs/toolkit';
+import { Meta, Story } from '@storybook/react';
+import React from 'react';
+import { Provider } from 'react-redux';
+import graphQueryResultSlice from '../../../../libs/shared/data-access/store/src/lib/graphQueryResultSlice';
 import { App } from './app';
 
 export default {
   component: App,
   title: 'App',
+  decorators: [
+    (story) => (
+      <div style={{ padding: '3rem' }}>
+        <Provider store={Mockstore}>{story()}</Provider>
+      </div>
+    ),
+  ],
 } as Meta;
 
 const Template: Story = (args) => <App {...args} />;
 
+// A super-simple mock of a redux store
+const Mockstore = configureStore({
+  reducer: {
+    graphQueryResult: graphQueryResultSlice,
+  },
+});
+
 export const Primary = Template.bind({});
 Primary.args = {};