Update dates.py to correct .scale

Author: smartlixx

lib/matplotlib/dates.py

@@ -826,7 +826,7 @@ class AutoDateFormatter(ticker.Formatter):
     A `.Formatter` which attempts to figure out the best format to use.  This
     is most useful when used with the `AutoDateLocator`.
 
-    `.AutoDateFormatter` has a ``.scale`` dictionary that maps tick scales (the
+    `.AutoDateFormatter` has a ``.scaled`` dictionary that maps tick scales (the
     interval in days between one major tick) to format strings; this dictionary
     defaults to ::