add support for xml and clover output

[mimmi20]

It would be helpful if this action would support the PHPUnits CLI Parameters "--coverage-clover" and "--coverage-xml".

[g105b]

Hi @mimmi20

Thank you for opening this. You should be able to pass any arguments to the script, but I'll look into this and provide an example at https://GitHub.com/php-actions/example-phpunit

I'm away this weekend but will pick up next week.

Greg.