Allow usage of namespace selection using wildcards

[naxvog]

As discussed in https://github.com/pestphp/pest/discussions/1072 and https://github.com/pestphp/pest/discussions/728 this PR allows the usage of wildcards in namespace selection.

This is useful if a module/domain architecture needs to be tested.

Tried to include globstar too but unfortunately symfony finder, as far as I know, does not support it.