On the front end, this changeset restores the theme's default border color when (and only when) the block's text color is the default.
In the editor, these styles repurpose the user-selected color for the border, to match the front.
Props nidhidhandhukiya, sabernhardt, pooja1210, pouicpouic, poena, shailu25, ugyensupport, wasiur195, rajinsharwar, wasiur195, jivygraphics, huzaifaalmesbah, harshgajipara, nicolefurlan, sumitbagthariya16.
Fixes#58022.
Built from https://develop.svn.wordpress.org/trunk@57587
git-svn-id: http://core.svn.wordpress.org/trunk@57088 1a063a9b-81f0-0310-95a4-ce76da25c4cd