Fix module imported twice

[valentinpalkovic]

Closes #21284

What I did

In Storybook 7.0 we use the new bootstrapApplication API to bootstrap a middleman Storybook Standalone Module to the DOM. The module is configured to respect your configured imports, declarations and schemas. This also means that there is no root ngModule anymore. Previously you could add ModuleWithProviders, likely the result of a 'Module.forRoot()'-style call, to your imports array of the moduleMetadata definition. This is now discouraged. Instead, you should use the new applicationConfig decorator to define application-wide providers and environment providers. Previously, we extracted all providers (and nested ones) from the modules, which were provided via imports automatically, which wasn't a clean solution and was causing bugs like #21284. Instead, now the user has to define all necessary environment-related providers manually.

For example, if you want to configure BrowserAnimationModule in your stories, please do the following:

import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
import { importProvidersFrom } from '@angular/core';
import { applicationConfig } from '@storybook/angular';
export default {
  title: 'Example',
  decorators: [
    applicationConfig({
      providers: [importProvidersFrom(BrowserAnimationsModule)],
    }),
  ],
};

You can also use the provide-style decorator to provide an application-wide service:

import { provideAnimations } from '@angular/platform-browser/animations';
import { applicationConfig } from '@storybook/angular';
export default {
  title: 'Example',
  decorators: [
    applicationConfig({
      providers: [provideAnimations()],
    }),
  ],
};

Please visit https://angular.io/guide/standalone-components#configuring-dependency-injection for more information.

Checklist

• Make sure your changes are tested (stories and/or unit, integration, or end-to-end tests)
• Make sure to add/update documentation regarding your changes
• If you are deprecating/removing a feature, make sure to update
  MIGRATION.MD

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  make sure to add the ci:merged or ci:daily GH label to it.
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["cleanup", "BREAKING CHANGE", "feature request", "bug", "documentation", "maintenance", "dependencies", "other"]