search: improvement of clickable areas of links
search: improvement of clickable areas of links

* Removes padding above and below links in result lists. This prevents
  the clickable areas from overlapping. Affects UX.

Signed-off-by: Marco Neumann <3829486b93ec44395f0b980424bae9b6fb07b7bc@crepererum.net>

tiborsimko/invenio-search,inveniosoftware/invenio-search,tiborsimko/invenio-search,inveniosoftware/invenio-search