Unecessary sleep when a connection needs to reauthenticate

[wolever]

client.Client will sleep for the backoff delay when it detects the need to reauthenticate:

    def _retry(self, reset_func, func, *args, **kwargs):
        backoff = self.starting_backoff
        while self.attempts <= self.retries or retried_auth:
            …
            try:
                …
            except ClientException as err:
                self._add_response_dict(caller_response_dict, kwargs)
                if err.http_status == 401:
                    if self.session:
                        should_retry = self.session.invalidate()
                    else:
                        # Without a proper session, just check for auth creds
                        should_retry = all((self.authurl, self.user, self.key))

                    self.url = self.token = self.service_token = None

                    if retried_auth or not should_retry:
                        raise
                    retried_auth = True
                …
            sleep(backoff)

This is, obviously, unnecessary.