Steps to reproduce the issue

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[5.5MiB/106.12s] Deprecation Notice: Class Joomla\Tests\Unit\Libraries\Cms\Table\TableTest located in C:/projects/joomla-cms/tests\Integration\Libraries\Cms\Table\TableTest.php does not comply with psr-4 autoloading standard. It will not autoload anymore in Composer v1.11+. in phar://C:/Tools/php/composer.phar/src/Composer/Autoload/ClassMapGenerator.php:185
[5.5MiB/106.13s] Deprecation Notice: Class Joomla\Tests\Unit\Libraries\Cms\Html\DocumentTest located in C:/projects/joomla-cms/tests\Unit\Libraries\Cms\Document\DocumentTest.php does not comply with psr-4 autoloading standard. It will not autoload anymore in Composer v1.11+. in phar://C:/Tools/php/composer.phar/src/Composer/Autoload/ClassMapGenerator.php:185
[5.6MiB/106.45s] Deprecation Notice: Class Joomla\CMS\Filesystem\Support\StringController located in C:/projects/joomla-cms/libraries/src\Filesystem\Support\Stringcontroller.php does not comply with psr-4 autoloading standard. It will not autoload anymore in Composer v1.11+. in phar://C:/Tools/php/composer.phar/src/Composer/Autoload/ClassMapGenerator.php:185
[5.7MiB/106.51s] Deprecation Notice: Class Joomla\CMS\Form\Rule\SubformRule located in C:/projects/joomla-cms/libraries/src\Form\Rule\SubFormRule.php does not comply with psr-4 autoloading standard. It will not autoload anymore in Composer v1.11+. in phar://C:/Tools/php/composer.phar/src/Composer/Autoload/ClassMapGenerator.php:185
[5.7MiB/106.52s] Deprecation Notice: Class Joomla\CMS\Filter\Image\Sketchy located in C:/projects/joomla-cms/libraries/src\Image\Filter\Sketchy.php does not comply with psr-4 autoloading standard. It will not autoload anymore in Composer v1.11+. in phar://C:/Tools/php/composer.phar/src/Composer/Autoload/ClassMapGenerator.php:185

These files/class names are all not case matching. We need to fix this to work on future versions of composer (and probably already cause issues in Linux vs Windows). This may also affect Joomla 3.x @HLeithner