Fixed cest filename

Before this fix, cest-classes filename was wrong, and for example in console output it was like this:
```
Trying to test basic crud operations of system client user (Codeception\TestCase\Cest::test_basic_crud_operations) - Ok
```
with this fix it is correct:
```
Trying to test basic crud operations of system client user (modules\users\CrudCest::test_basic_crud_operations) - Ok
```