make doLoadClassMetadata() methods private

Author: xabbuh

Mapping/Loader/AttributeLoader.php

@@ -59,7 +59,7 @@ public function loadClassMetadata(ClassMetadata $metadata): bool
         return $success;
     }
 
-    public function doLoadClassMetadata(\ReflectionClass $reflClass, ClassMetadata $metadata): bool
+    private function doLoadClassMetadata(\ReflectionClass $reflClass, ClassMetadata $metadata): bool
     {
         $className = $reflClass->name;
         $success = false;