Draft: [CI] CTest xdmfdiff with timestep
The options [--timestep-b <TIMESTEP>] [--timestep-a <TIMESTEP>]
were not considered within CTests, when the tester is xmdfdiff
. By default time step 0 was taken.
Now, all XDMF related CTests require the specification of the time step to be compared as 7th and 8th parameter.