Bug 29803: Do not wait for the images more than 5 seconds

Bug 29803: Do not wait for the images more than 5 seconds

In case of the previous bug, the page was calling the callback function
every 100ms, endlessly. We should add a test to prevent future similar
problem.

Test plan:
Remove the previous patch "Prevent local cover image to be hidden if
Coce is enabled"
Recreate the test plan
=> You should see the local image displayed after 5 seconds, and a
log in the JS console

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>