fix: :bug: Handle case sensitivity on different OS's

[KPLauritzen]

Fix #20

[olzhasar]

Hi @KPLauritzen ,

Sorry for the late reply, I had a very busy period.

Even though your PR solves the specific issue that you mentioned, I hesitate to merge it because of the ability to have case- insensitive and sensitive paths at the same time in Windows.

Implementing a checking mechanism for that looks an overkill for a project like pytest-watcher.

I personally do not use Windows, so I don't have a strong opinion about things. Do you think case-sensitive situations can be neglected in Windows?

[olzhasar]

Closing this for the lack of activity. Feel free to reopen