A transport layer timeout is made independent of the query timeout,
i.e. the maximum time to wait for the query to complete.

The query timeout is used by the blocking poll so that the backend
does not block for too long when polling for job completion, but
the transport can have different timeout requirements, and we do
not want it to be raising sometimes unnecessary timeout errors.

As job methods do not split the timeout anymore between all requests a
method might make, the Client methods are adjusted in the same way.