Replace pearson correlation function from SciPy with the one from Numpy

[RalfG]

Can this line:

DeepLCRetrainer/deeplcretrainer/cnn_functions.py

Line 1148 in 5fe5d80

corr = scipy.stats.pearsonr(y, pred_test)[0]

be replaced with:

np.corrcoef(y, pred_test)[0][1]

to avoid the SciPy dependency? As far as I can see, this is the only place SciPy is used.