Fixed another test for np.int8

4 jobs for master in 3 minutes and 17 seconds
Status Job ID Name Coverage
  Test
passed #202636
test_minimal

00:00:34

passed #202637
test_mpi

00:02:25

passed #202638
test_mpi_fftw

00:02:08

passed #202639
test_mpi_fftw_hdf5

00:03:16