[5.x] Fix add set button not overlap content on small container

[lecoa]

This PR resolves: https://github.com/statamic/cms/issues/13270

When the bard field is less then 32 rem wide the content has reduced padding, resulting in the bard add set button overlapping with the content. https://github.com/statamic/cms/blob/566eb8ba117d15e471ba48a0424a7332cb9f359d/resources/css/components/fieldtypes/bard.css#L11-L14

This PR resolves this by moving the button when the width is smaller.

Currently overlapping:

What this PR resolves: