Description:
------------
The Brazilian DST for 2018 is scheduled to start at November 4, 2018 [1].
But it still think it starts on October 21. 

Affected versions:
- PHP 7.0.32
- PHP 7.1.23
- PHP 7.2.11

[1]: https://www.timeanddate.com/news/time/brazil-delays-dst-2018.html

Test script:
---------------
ini_set('date.timezone', 'UTC');
$cal = new IntlGregorianCalendar(2018, 9, 22, 12, 0, 0);

//echo IntlDateFormatter::formatObject($cal, 'Y-M-d h:mm:ss Z (z)')."\n";
//Output 2018-10-22 12:00:00 +0000 (UTC)

$cal->setTimeZone('America/Sao_Paulo');

echo IntlDateFormatter::formatObject($cal, 'Y-M-d h:mm:ss Z (z)')."\n";
//Output 2018-10-22 10:00:00 -0200 (BRST)
//Should output 2018-10-22 09:00:00 -0300 (BRT)