Bug 27029: Add data-biblionumber attribute to OPAC detail page

Bug 27029: Add data-biblionumber attribute to OPAC detail page

This patch adds a data-biblionumber attribute to the
div#catalogue_detail_biblio elements on opac-detail.pl, so that
Javascript running on the page can easily fetch and use the
record's biblionumber.

Signed-off-by: Mark Hofstetter <mark@hofstetter.at>, <koha@trust-box.at>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
(cherry picked from commit f17a631d873f971ac139534fc2867c7ac86b7bd5)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>