Fix case in composer.json to resolve packagist warning:
Fix case in composer.json to resolve packagist warning:

Skipped branch main, Invalid package information:
Deprecation warning: require-dev.phpunit/PHPUnit is invalid, it should not contain uppercase characters. Please use phpunit/phpunit instead. Make sure you fix this as Composer 2.0 will error.

soliantconsulting/SimpleFM