Adjust CSS for "Moved to the trash" message for a pingback in the dashboard.

Props zoerooney, codenameEli.
Fixes #28286.

Built from https://develop.svn.wordpress.org/trunk@28811


git-svn-id: http://core.svn.wordpress.org/trunk@28619 1a063a9b-81f0-0310-95a4-ce76da25c4cd