Bug 31439: Use pseudo element for bullet in results.tt

Bug 31439: Use pseudo element for bullet in results.tt

To test:
1. Apply patch and regenerate CSS. See:
  https://wiki.koha-community.org/wiki/Working_with_SCSS_in_the_OPAC_and_staff_client
2. Go to the staff results page and inscept the result_item_details
   class.
3. It should contain a ::before pseudo element that is the bullet point.
4. This is easier to remove of alter with the following CSS in
   IntraNetUSerCSS:

.result_item_details::before {
	content: " " !important;
}

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>