test(database): address transaction callback review notes

Signed-off-by: memleakd <121398829+memleakd@users.noreply.github.com>

Author: memleakd

tests/system/Database/Live/TransactionCallbacksTest.php

@@ -23,11 +23,9 @@
 
 /**
  * @internal
- *
- * @no-final
  */
 #[Group('DatabaseLive')]
-class TransactionCallbacksTest extends CIUnitTestCase
+final class TransactionCallbacksTest extends CIUnitTestCase
 {
     use DatabaseTestTrait;
 

user_guide_src/source/database/transactions/011.php

@@ -1,5 +1,9 @@
 <?php
 
 $this->db->afterCommit(static function (): void {
-    // Runs immediately because there is no active transaction.
+    // Runs immediately because no transaction has started yet.
 });
+
+$this->db->transStart();
+$this->db->query('AN SQL QUERY...');
+$this->db->transComplete();