+ [misc] Add unit tests for instanceModel::deleteBackupCron() method

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

module/instance/test/lib/instance.unittest.class.php

@@ -498,4 +498,19 @@ class instanceTest
 
         return $result;
     }
+
+    /**
+     * Test deleteBackupCron method.
+     *
+     * @param  object $instance
+     * @access public
+     * @return bool
+     */
+    public function deleteBackupCronTest(object $instance): bool
+    {
+        $result = $this->objectModel->deleteBackupCron($instance);
+        if(dao::isError()) return dao::getError();
+
+        return $result;
+    }
 }