Skip \Drupal\Tests\file\Kernel\Views\RelationshipUserFileDataTest on PostgreSQL

(cherry picked from commit 99b1114f)

core/modules/file/tests/src/Kernel/Views/RelationshipUserFileDataTest.php

@@ -4,6 +4,7 @@
 
 namespace Drupal\Tests\file\Kernel\Views;
 
+use Drupal\Core\Database\Database;
 use Drupal\field\Entity\FieldConfig;
 use Drupal\field\Entity\FieldStorageConfig;
 use Drupal\file\Entity\File;
@@ -50,6 +51,10 @@ class RelationshipUserFileDataTest extends ViewsKernelTestBase {
   protected function setUp($import_test_views = TRUE): void {
     parent::setUp($import_test_views);
 
+    if (Database::getConnection()->driver() === 'pgsql') {
+      $this->markTestSkipped('Skipped because PostgreSQL is currently failing: https://www.drupal.org/project/drupal/issues/3364621');
+    }
+
     $this->installSchema('file', ['file_usage']);
     $this->installEntitySchema('user');
     $this->installEntitySchema('file');