doc: corrected default value for flipped in core/image/__init__.py

Author: Zen-CODE

kivy/core/image/__init__.py

@@ -790,7 +790,7 @@ def save(self, filename, flipped=False):
         Any other extensions are not officially supported.
 
         The flipped parameter flips the saved image vertically, and
-        defaults to True.
+        defaults to False.
 
         Example::