[1.13] Allow setting cookie session=false

[divinity76]

Previously

$page->setCookies([
    \HeadlessChromium\Cookies\Cookie::create("session_false", "session_false", ["session" => false, "domain" => "example.com"]),
    \HeadlessChromium\Cookies\Cookie::create("session_true", "session_true", ["session" => true, "domain" => "example.com"]),
])->await();

would create 2 cookies with session=true, but now it will create 1 cookie with session=false and 1 with session=true

close GH-675

[GrahamCampbell]

This PR contains unrelated changes. I'm going to put in the

            if (!isset($cookie['expires']) && ($cookie['session'] ?? null) === false) {
                $browserCookie['expires'] = \time() + (1 * 60 * 60 * 24 * 365);
            }

change, only.