Bug 30958: OPAC overdrive search result page broken for translations

Bug 30958: OPAC overdrive search result page broken for translations

Note: You will need a valid OverDrive subscription to test this.

This patch fixes a JavaScript error thrown on the OPAC overdrive search
results page for libraries using translation templates and who don't
have the OverDrivePasswordRequired system preference = 'Required'.

Test plan:
1. Install the en-NZ translation: https://wiki.koha-community.org/wiki/Installation_of_additional_languages_for_OPAC_and_INTRANET_staff_client

2. Enable the en-NZ language:
   - In the OPACLanguages system preference -> tick 'English New Zealand
     (en-NZ)' checkbox and untick 'English (en)'

3. Fill in the OverDrive system preferences:
   - Make sure you set: OverDrivePasswordRequired = "Not required"

4. Perform an OPAC search

5. Click on the Overdrive results link

6. Open the browser console and notice there is a JS error, and the
   OverDrive results do not load

7. Apply patch

8. Update the en_NZ translation:

9. Repeat steps 4, 5 and 6 and notice there is no JavaScript error and
   the OverDrive results do display

Sponsored-by: Melbourne Athenaeum Library, Australia
Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>