MC-5232: Prefix field names with section name to avoid field name collision

- Fix namespace on integration test

Author: davemacaulay

dev/tests/integration/testsuite/Magento/PageBuilder/Model/Stage/Config/UiComponentConfigTest.php

@@ -6,7 +6,7 @@
 
 declare(strict_types=1);
 
-namespace Magento\PageBuilder\Model\Stage;
+namespace Magento\PageBuilder\Model\Stage\Config;
 
 use Magento\TestFramework\Helper\Bootstrap;