urlrequest: prefer to use resp_status

Author: tito

kivy/network/urlrequest.py

@@ -332,7 +332,8 @@ def wait(self, delay=0.5):
 
         .. versionadded:: 1.0.10
         '''
-        while self._dispatch_result(delay) is None:
+        while self.resp_status is None:
+            self._dispatch_result(delay)
             sleep(delay)