0.8dev: Removed duplicate linking of `diff.css` stylesheet in `bh_diff_view.html`, as was done for `diff.html` in [trac 12337]. Refs trac:#11406.


git-svn-id: https://svn.apache.org/repos/asf/bloodhound/trunk@1551551 13f79535-47bb-0310-9956-ffa450edef68