fix: Attribute OL with the domain we arrived at

Relevant library snippet -- we get the response from the final destination that we arrived at when being redirected:

[snip]
var shouldRedirect bool
redirectMethod, shouldRedirect, includeBody = redirectBehavior(req.Method, resp, reqs[0])
if !shouldRedirect {
    return resp, nil
}

(From client.go in package http).

Part of #1 (closed).