Unclear documentation

I added a comment in https://www.drupal.org/project/storybook/issues/3490944#comment-15934552 💬 Testing Storybook sdc_examples: my-banner Storybook is blank page Active that might be helpful. I'm repeating the last part for convenience here:

@yevko: I'm able to include/embed SDC components, e.g., `{% include('sdc_examples:my-button') %}` but as soundvox indicated, it looks like you have to use either an SDC template or a Twig template that is registered with Drupal. If you're using an existing Drupal theme, it may already be registered and you can use the appropriate namespace, e.g., `{% include '@mytheme/path/to/mytemplate.twig' %}`.

I've created an MR to "Add some troubleshooting cases to README" in case it's helpful for anyone.