code: public function setCookie(HttpHeaders $headers, Cookie $cookie): void
      {
          $headers->add('Set-Cookie', $this->getSetCookieHeaderValue($cookie), true);
      }
docs: Sets a cookie in the headers
  
  @param HttpHeaders $headers The headers to set the cookie in
  @param Cookie $cookie The cookie to set
  @throws RuntimeException Thrown if the set cookie header's hash key could not be calculated