only do dict comparisons if not tainted

wp_oauth_backend/wp_oauth.py

@@ -152,6 +152,7 @@ class StepwiseMathWPOAuth2(BaseOAuth2):
             ))
             tainted = True
 
+        if not tainted:
             # a def in the third_party_auth pipeline list calls get_user_details() after its already
             # been called once. i don't know why. but, it passes the original get_user_details() dict
             # enhanced with additional token-related keys. if we receive this modified dict then we