PSR-4 warning when installing CI4 via Composer

The warnings appear in Composer 2.7.7.
The warnings are correct, so we cannot say it is a bug in Composer.

But there is nothing wrong. They just say skipped to add the classes to the class map.

Thanks @kenjis, so this warning is ignorable? Sorry I thought it's a bug in Composer, CI4 is running fine although it has this warnings.