reduced the noise in the noisy test because with float32 the ffts are more fragiles

nabu/preproc/tests/test_alignment.py

@@ -147,7 +147,7 @@ class TestCor(object):
         radio1 = self.data[0, :, :]
         radio2 = np.fliplr(self.data[1, :, :])
 
-        noise_level = radio1.max() / 8.0
+        noise_level = radio1.max() / 16.0
         noise_ima1 = np.random.normal(0.0, size=radio1.shape) * noise_level
         noise_ima2 = np.random.normal(0.0, size=radio2.shape) * noise_level