Tests of functional/03-xc.XXX should not write restart
At the moment each test affects the next by writing its own restart. This is inefficient because this takes time, but also makes each subtest a bit useless as it accumulates errors and differences from prior tests. In particular the first time we call Hartree, Hartree-Fock or an hybrid functional, we get a GPU-CPU splitting which is due to the Poisson solver.
We should add RestartWrite=no
to all these tests except the first one. This would make the test faster and more informative