Using MEDIUM size for dates in format so it doesn't lose anymore reference in 2099.

Author: marcoaacoliveira

lib/internal/Magento/Framework/Stdlib/DateTime/Timezone.php

@@ -362,7 +362,7 @@ private function appendTimeIfNeeded($date, $includeTime, $timezone, $locale)
 
             $formatterWithoutHour = new \IntlDateFormatter(
                 $locale,
-                \IntlDateFormatter::SHORT,
+                \IntlDateFormatter::MEDIUM,
                 \IntlDateFormatter::NONE,
                 new \DateTimeZone($timezone)
             );
@@ -379,7 +379,7 @@ private function appendTimeIfNeeded($date, $includeTime, $timezone, $locale)
 
             $formatterWithHour = new \IntlDateFormatter(
                 $locale,
-                \IntlDateFormatter::SHORT,
+                \IntlDateFormatter::MEDIUM,
                 \IntlDateFormatter::SHORT,
                 new \DateTimeZone($timezone)
             );