Dropdown shortcode handle markdown correctly

Karl

15.40.2020 ec011355942d1b8612c61664a4e0a37d86339fdd

 layouts/shortcodes/dropdown.md

@@ -1,4 +1,4 @@
<details>
    <summary>{{ .Get "summary" }}</summary>
    {{ .Inner }}
    {{ .Inner | markdownify }}
</details>