refactor(demo): hero-banner optional/mandatory knobs - FRONT-912

[Joosthe]

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• I have put the vanilla component as devDependencies
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• I have added the components directly used in the twig file (with include or embed) as dependencies
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[Joosthe]

@planctus Looks really much improved and thanks for all the work, the only thing i could find on the component is that the icon is missing now in the preview of the component

[planctus]

No, @Joosthe , the icon is there:
https://5e73a38ee6b9de0ee0b17d46--ecl-twig.netlify.com/ec/?path=/story/components-banners-hero-banner--image
I think you just need to update the plugin for the story-utils, sorry not to point this out in advance, but as usual, when we have changes in one of our plugins we need to pay attention to really update it on our local environments.
So, you can remove the node-modules folder and run yarn again or you can copy the index.js file from the working tree (utils/story-utils/src/index.js) to the package in the node_modules folder (node-modules/@ecl-twig/story-utils/src/index.js).
I hope this is the last time i have to write this, but it's true that might maybe find a solution for this beacuse i see that everytime is an issue.