Sync parameter order in boston_housing with reuters (#8326)

keras/datasets/boston_housing.py

@@ -2,15 +2,15 @@
 import numpy as np
 
 
-def load_data(path='boston_housing.npz', seed=113, test_split=0.2):
+def load_data(path='boston_housing.npz', test_split=0.2, seed=113):
     """Loads the Boston Housing dataset.
 
     # Arguments
         path: path where to cache the dataset locally
             (relative to ~/.keras/datasets).
+        test_split: fraction of the data to reserve as test set.
         seed: Random seed for shuffling the data
             before computing the test split.
-        test_split: fraction of the data to reserve as test set.
 
     # Returns
         Tuple of Numpy arrays: `(x_train, y_train), (x_test, y_test)`.