Custom file picker validation message overlaps any following content

noticed while working on a separate PR in master/v5: using validation messages with a custom file picker, the validation message overlaps any content that follows.

tested quickly using one of the deploy previews https://twbs-bootstrap.netlify.com/docs/4.3/forms/validation/#supported-elements and moving the textarea example after the file picker.

this is a regression from v4, where this is not a problem https://getbootstrap.com/docs/4.4/components/forms/#supported-elements