List of file types is displayed outside the form

### Description of the bug

When adding a long list of file types to an upload in validFileEndings in ui/form/layouts, the list will be displayed outside the form.

### Steps To Reproduce

1. Go to a component for file upload in the code, for example ui/form/layouts/Anleggbidrag.json in https://altinn.studio/repos/nve/nve-0030.
2. Add a long list of valid file endings to "validFileEndings" and set "hasCustomFileEndings": true.
3. In the app, the list will be displayed outside the form (see image below):

### Additional Information

_No response_

Reproduce the issue using ui/form/layouts/Anleggbidrag.json with a long validFileEndings list and hasCustomFileEndings set to true. Start by tracing how this upload configuration is rendered in the app frontend. Done means the complete list remains inside the form when displayed.

Written by the indexing model from the issue text.