Update PHPStanPHPUnitExtension.php

Author: staabm

src/Testing/PHPUnit/PHPStanPHPUnitExtension.php

@@ -18,6 +18,8 @@ public function bootstrap(
 		ParameterCollection $parameters,
 	): void
 	{
+		// use multiple subscribers which all initialize the test-container.
+		// we need to make sure we only initialize once per test-class.
 		$facade->registerSubscriber(
 			new InitContainerBeforeDataProviderSubscriber(),
 		);