Improve filtering of items

[arogachev]

Q	A
Is bugfix?	❌
New feature?	❌
Breaks BC?	❌

[what-the-diff]

PR Summary

• Simplified Array Filtering in FakeItemsStorage.php
  The logic for filtering arrays in both filterRoles and filterPermissions methods has been improved. The old method, which relied on checking if an array key exists, has been replaced with a more straightforward approach: now it checks directly if an item is an instance of Role or Permission respectively. It will make the code more readable and easier to maintain.