Fix date format for different locales

Author: bnymn

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

@@ -309,11 +309,23 @@ public function formatDateTime(
      */
     public function convertConfigTimeToUtc($date, $format = 'Y-m-d H:i:s')
     {
+        $formatter = new \IntlDateFormatter(
+            $this->_localeResolver->getLocale(),
+            \IntlDateFormatter::MEDIUM,
+            \IntlDateFormatter::MEDIUM,
+            $this->getConfigTimezone(),
+            null,
+            null
+        );
+        $unixTime = $formatter->parse($date);
+        $dateTime = new DateTime($this);
+
         if (!($date instanceof \DateTimeInterface)) {
             if ($date instanceof \DateTimeImmutable) {
                 $date = new \DateTime($date->format('Y-m-d H:i:s'), new \DateTimeZone($this->getConfigTimezone()));
             } else {
-                $date = new \DateTime($date, new \DateTimeZone($this->getConfigTimezone()));
+                $dateUniversal = $dateTime->gmtDate(null, $unixTime);
+                $date = new \DateTime($dateUniversal, new \DateTimeZone($this->getConfigTimezone()));
             }
         } else {
             if ($date->getTimezone()->getName() !== $this->getConfigTimezone()) {