Bug 24373: Correct basic cataloging editor CSS

Bug 24373: Correct basic cataloging editor CSS

This patch makes minor corrections to the basic MARC editor CSS, fixing
an error caused by Bug 23259.

To test, apply the patch and clear your browser cache if necessary.

Open the basic MARC editor and check the numbered tabs. There should be
no stripe of green background showing below the tabs.

Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
Signed-off-by: Guillaume Paquet <guillaume@inlibro.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>