Bug 32926: Assign unique ids to <h3> elements

Bug 32926: Assign unique ids to <h3> elements

If you perform a System preferences search for a common word
such as "type", you lose the ability to expand or collapse some
sections. In particular, you cannot expand/collapse the sections
with names that appear more than once in the results page.
All sections except the first one in each group of duplicates
are affected by this. See https://imgur.com/a/NSslIcV for a demo.

This patch fixes that by prepending the <h3> ids with the
top-level System preference section name to make them unique.

Test plan:

1) Perform a System preferences search for a common word such
   as "type" or "log". In the results page, the "Policy" section
   will appear more than once. Now try to expand/collapse any
   "Policy" section but the first one. It won't work, only the
   first "Policy" section is toggled.
2) Apply this patch and refresh the page.
3) This time you should be able to expand or collapse all of
   the available system preference sections.
4) Clicking on the "View all xxx preferences" links on the
   right hand side should take you to the correct System
   preferences tab *and* automatically scroll the appropriate
   section into view at the top of the page.

Signed-off-by: Fridolin <fridolin.somers@biblibre.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>