Fix linting error

Author: hexgnu

pandas/core/sparse/array.py

@@ -255,7 +255,7 @@ def memory_usage(self, deep=False):
         Notes
         -----
         Memory usage does not include memory of empty cells filled by
-        fill_value. And it does not include memory consumed by 
+        fill_value. And it does not include memory consumed by
         elements that are not components of the array if deep=False
 
         See also