Bug 34223: (follow-up) Mock backend in tests

Bug 34223: (follow-up) Mock backend in tests

Add a new request with a backend specific status

Signed-off-by: Pedro Amorim <pedro.amorim@ptfs-europe.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
(cherry picked from commit b00806774d3353086fc7c7e3def22f4de570c795)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>
(cherry picked from commit 6151e6ee8cfb309412727c5bf3383eb2d9464fbe)
Signed-off-by: Matt Blenkinsop <matt.blenkinsop@ptfs-europe.com>