[tests] Add global phpunit install test

[TomasVotruba]

Spotted in tempestphp/tempest-framework#1635

composer global require phpunit/phpunit

phpunit tests

This should pass as well.

[TomasVotruba]

@samsonasik Could you look into this one? The global PHPUnit is causing tempestphp/tempest-framework#1635 error

[samsonasik]

@TomasVotruba yes, I created test for it at:

• Add test for require global install for PHPUnit 12 #3

[TomasVotruba]

Resolved in #3