Bug 31228: Intranet coce.js is not hiding the coce-coverimg div for single-pixel...

Bug 31228: Intranet coce.js is not hiding the coce-coverimg div for single-pixel image

This is because the intranet detail.tt has coce-coverimg as an ID.
Intranet results.tt has coce-coverimg as a class. Intranet coce.js
targets coce-coverimg as a class.

Intranet detail.tt should be changed to have coce-coverimg as a class.
This is inline with the change made to the OPAC in bug 31217

Test plan:
1. Set your system preferences:
- CoceHost = https://coce.mykoha.co.nz
- CoceProviders = Select all
- IntranetCoce = Enable

2. Add the ISBN of '9780262336499' to a biblio

3. Open a "Incognito" window in your browser (recommended to use Google
Chrome to test this)

4. View the biblio detail page in the intranet. Observe a 'Coce image
from Amazon' box loads with a spinner

5. Apply patch and restart services

6. Clear your browser cache

7. Reload the same biblio detail page in the intranet. Observe no image
is displayed.

8. Do an intranet search to get the biblio returned in search results
page. Confirm no cover image box is displayed

9. View the intranet search result and detail pages for a different
biblio that you know Coce should be displaying the cover image of and
confirm that it is correctly displayed with the source of that image
listed: For example 'Coce image from Amazon.com' is displayed

Sponsored-by: Catalyst IT, New Zealand
Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>