Fix functional tests for Category Collection
Right now functional tests for category collection are skipped.
We need to rewrite them to use functional testing framework and enable them again.
[TASK] Fix category collection functional test
Category collection test now extends FunctionalTestCase
class and is green again.
Reviewed-by: Oliver Klee
Reviewed-by: Marc Bastian Heinrichs
Tested-by: Marc Bastian Heinrichs
Reviewed-by: Marcin Sągol
Tested-by: Marcin Sągol
Reviewed-by: Fabien Udriot
Reviewed-by: Francois Suter
Tested-by: Francois Suter