Fix: Remove accessibility modification for cache property in non-serializable object test

Author: Infinite-Null

tests/phpunit/tests/cache.php

@@ -539,7 +539,6 @@ public function test_stats_with_non_serializable_simplexml_data() {
 		// any object-clone logic in set(), simulating a real-world scenario where
 		// a non-serializable object ends up in the cache.
 		$cache_property = new ReflectionProperty( $this->cache, 'cache' );
-		$cache_property->setAccessible( true );
 		$cache_data                       = $cache_property->getValue( $this->cache );
 		$cache_data['xml-group']['item1'] = $xml_object;
 		$cache_property->setValue( $this->cache, $cache_data );