Bug 31749: Fix detail display when not display cover images
To test:
1. Apply patch
2. Have none of the image services turned on:
AmazonCoverImages
LocalCoverImages
IntranetCoce
SyndeticsCovers
3. Look at the detail page, things should look right.
4. Turn on some of these image services, things should still look right.
Signed-off-by: Julian Maurice <julian.maurice@biblibre.com> Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com> Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>