This fix brokes border between card-header and list-group, it's doubled in 4.5.0.

This fix brokes border between card-header and list-group, it's doubled in 4.5. See diffierence... https://getbootstrap.com/docs/4.4/components/card/#list-groups https://getbootstrap.com/docs/4.5/components/card/#list-groups

Originally posted by @waclaw66 in https://github.com/twbs/bootstrap/pull/30497#issuecomment-627523760