Bug 10653: add unit tests for C4::RotatingCollections.pm

Bug 10653: add unit tests for C4::RotatingCollections.pm

The tests are wrap in a database transaction.

Test plan:
prove t/db_dependent/RotatingCollections.t
t/db_dependent/RotatingCollections.t .. ok
All tests successful.
Files=1, Tests=41, 20 wallclock secs ( 0.02 usr  0.01 sys +  0.41 cusr  0.02 csys =  0.46 CPU)
Result: PASS

Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>
(cherry picked from commit 12061f44beb46709e03d09f7ff61551fa9297b2e)
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>