Bug 34074: Improve translations of strings on the about page

Bug 34074: Improve translations of strings on the about page

This patch makes a few simple changes to the about page template to
improve how the translation tool picks up strings to translate.

The patch also corrects a couple of lines where template tags contained
line breaks.

To test, apply the patch and view the about page in the staff interface.
Everything should look correct.

Signed-off-by: Sam Lau <samalau@gmail.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>