Nightlies are failing on py37 because of this

Reference: https://gitlab.idiap.ch/bob/bob.nightlies/-/jobs/172023

Error message:

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ERROR: bob.learn.em.test.test_plda_trainer.test_plda_EM_vs_Prince
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Traceback (most recent call last):
  File "/scratch/builds/bob/bob.nightlies/miniconda/conda-bld/bob.learn.em_1567458302299/_test_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_plac/lib/python3.7/site-packages/nose/case.py", line 197, in runTest
    self.test(*self.arg)
  File "/scratch/builds/bob/bob.nightlies/miniconda/conda-bld/bob.learn.em_1567458302299/_test_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_plac/lib/python3.7/site-packages/bob/learn/em/test/test_plda_trainer.py", line 534, in test_plda_EM_vs_Prince
    t_py.initialize(m_py,l)
  File "/scratch/builds/bob/bob.nightlies/miniconda/conda-bld/bob.learn.em_1567458302299/_test_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_plac/lib/python3.7/site-packages/bob/learn/em/test/test_plda_trainer.py", line 154, in initialize
    self.__init_members__(data)
  File "/scratch/builds/bob/bob.nightlies/miniconda/conda-bld/bob.learn.em_1567458302299/_test_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_plac/lib/python3.7/site-packages/bob/learn/em/test/test_plda_trainer.py", line 60, in __init_members__
    self.m_sum_z_second_order.resize(df_dg, df_dg)
ValueError: cannot resize an array that references or is referenced
by another array in this way.
Use the np.resize function or refcheck=False