Merge branch '6.4' into 7.2

* 6.4:
  skip test if the installed ICU version is too modern

Author: nicolas-grekas

Tests/Extension/Core/DataTransformer/DateTimeToLocalizedStringTransformerTest.php

@@ -16,6 +16,7 @@
 use Symfony\Component\Form\Extension\Core\DataTransformer\BaseDateTimeTransformer;
 use Symfony\Component\Form\Extension\Core\DataTransformer\DateTimeToLocalizedStringTransformer;
 use Symfony\Component\Form\Tests\Extension\Core\DataTransformer\Traits\DateTimeEqualsTrait;
+use Symfony\Component\Intl\Intl;
 use Symfony\Component\Intl\Util\IntlTestHelper;
 
 class DateTimeToLocalizedStringTransformerTest extends BaseDateTimeTransformerTestCase
@@ -235,6 +236,10 @@ public function testReverseTransformFullTime()
 
     public function testReverseTransformFromDifferentLocale()
     {
+        if (version_compare(Intl::getIcuVersion(), '71.1', '>')) {
+            $this->markTestSkipped('ICU version 71.1 or lower is required.');
+        };
+
         \Locale::setDefault('en_US');
 
         $transformer = new DateTimeToLocalizedStringTransformer('UTC', 'UTC');