Add border width utility

Created by: MauricioHernanCabrera

I added border-width utility. it was a request https://github.com/twbs/bootstrap/issues/31299

Example

<div class="border border-primary border-width-5">Hello world</div>

<div class="border border-primary border-width-2">Hello world</div>

Fixes #31299 (closed)

Demo: https://deploy-preview-31484--twbs-bootstrap.netlify.app/docs/5.0/utilities/borders/#border-width