Bug 27740: (follow-up) quote of the day to <h2>

Bug 27740: (follow-up) quote of the day to <h2>

If the quote of the day feature is enabled, a "Quote of the day" heading
is displayed. It was an <h3> which was not proper hierarchy, so this has
been changed to an <h2>.

To test:
1) Go to staff client
2) Enable quote of the day preference
3) Go to the OPAC
4) Observe "Quote of the day" heading
5) Ensure it is an <h2>

Sponsored-by: Catalyst IT
Signed-off-by: Henry Bolshaw <bolshawh@parliament.uk>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>