Featherlight plugin - gallery not working

Since learn2 adds featherlight as standard asset and adds some featherlight related code in the learn.js file, the gallery activated in the plugin settings breaks/does not work and the featherlight scripts are loaded multiple times.

Remove this from **learn.js**

```
$(function() {
$('a[rel="lightbox"]').featherlight({
root: 'section#body'
});
});
```

And kill
```
{% do assets.addJs('theme://js/featherlight.min.js') %}
{% do assets.addCss('theme://css/featherlight.min.css') %}
```
from **base.html.twig**.

After this, i successfully set up a featherlight gallery.

Inspect the Featherlight initialization in learn.js and the asset additions in base.html.twig. Remove the duplicated setup described in the issue, then verify that a gallery enabled in the plugin settings works and that Featherlight scripts are not loaded multiple times.

Written by the indexing model from the issue text.