fix(Session): send SameSite attribute in BaseHandler::destroyCookie() - #10748

Description
BaseHandler::destroyCookie() did not include the SameSite attribute in the $options array passed to setcookie(), while Session::configure() and Session::setCookie() set it according to Config\Cookie::$samesite. This change stores $cookieSameSite from Config\Cookie and passes it when destroying the cookie, defaulting empty values to Lax.

Checklist:

• Securely signed commits
• Component(s) with PHPDoc blocks, only if necessary or adds value (without duplication)
• Unit testing, with >80% coverage
• User guide updated
• Conforms to style guide