Fix typo

Fix "contorls" to "controls" in window_text docstring

Author: beuaaa

pywinauto/base_wrapper.py

@@ -307,7 +307,7 @@ def window_text(self):
         """
         Window text of the element
 
-        Quite a few contorls have other text that is visible, for example
+        Quite a few controls have other text that is visible, for example
         Edit controls usually have an empty string for window_text but still
         have text displayed in the edit window.
         """