Fix typo in issues Update request

Fix typo `lables` in issues update request. Fixes #45
copitux · rjmackay · Aug 23, 2015 · Aug 23, 2015 · 52a3ed27f6c4ebf6d81ea7c872f301ec4fda88b1
commit 52a3ed27f6c4ebf6d81ea7c872f301ec4fda88b1
diff --git a/pygithub3/requests/issues/__init__.py b/pygithub3/requests/issues/__init__.py
@@ -39,6 +39,6 @@ class Update(Request):
     resource = Issue
     body_schema = {
         'schema': ('title', 'body', 'assignee', 'state', 'milestone',
-                   'lables'),
+                   'labels'),
         'required': ()
     }