TS-4396: fix number_of_redirections off-by-one

[mingzym]

please test

[jpeach]

Right below here, we repeat the test on number_of_redirections with is_redirect_required(). The condition is different however, since this code will not redirect withnumber_of_redirectionsandis_redirect_required()`` will.

I don't think that this is the right place to increment redirection_tries, though it is an improvement. How about incrementing it in redirect_request()? Or at least defer until we know we are actually going to call redirect_request.

We should restructure this function like this:

if (!is_redirect_required()) {
    tunnel.deallocate_redirect_post_buffers();
    enable_redirection = false;
    return;
}

...

[mingzym]

hmm, looks like better to do redirection_tries++ when setting redirect_in_process = true, if you consider a really redirection. good catch.

[PSUdaemon]

[approve ci]

[bryancall]

Closing since there is a new PR for this #2092