Issue #3239466: Refactor build tests to use core-supported project templates

tests/src/Build/CoreUpdateTest.php

@@ -9,9 +9,15 @@ namespace Drupal\Tests\automatic_updates\Build;
  */
 class CoreUpdateTest extends UpdateTestBase {
 
+  /**
+   * {@inheritdoc}
+   */
   protected function getInitialConfiguration(array $data): array {
     $data = parent::getInitialConfiguration($data);
+    unset($data['require']['drupal/core-vendor-hardening']);
+    unset($data['require']['drupal/core-project-message']);
     unset($data['require-dev']);
+    unset($data['conflict']);
     return $data;
   }