Robocop matches paths from gitignore in every directory

Given the following gitignore:

```
file.robot
browser/
some/**/path
```

Robocop ignores all above paths, but in every directory - for example browser/ will be ignored if it's placed in other/browser path as well. I need to investigate how the gitignore is working and only ignore paths ignored by git.

Start by tracing Robocop's gitignore handling and compare its path matching with Git's behavior for the shown patterns. Reproduce the examples with file.robot, browser/, and some/**/path in nested directories; done means only paths Git would ignore are excluded.

Written by the indexing model from the issue text.