Fix doctest failure.

doc/tutorial/statistical_inference/model_selection.rst

@@ -198,8 +198,8 @@ automatically by cross-validation::
         n_alphas=100, normalize=False, precompute='auto', tol=0.0001,
         verbose=False)
     >>> # The estimator chose automatically its lambda:
-    >>> lasso.alpha
-    0.013180196198701137
+    >>> lasso.alpha # doctest: +ELLIPSIS
+    0.01318...
 
 These estimators are called similarly to their counterparts, with 'CV'
 appended to their name.