Always ignore the .git directory in file picker

[EpocSquadron]

Some users (including myself) want to turn off filtering of files
prefixed with ., as they are often useful to edit. For example, .env
files, configuration for linters .eslint.json and the like.

[archseer]

To see those it should be enough to turn on hidden files but keep the ignore/gitignore setting.

[EpocSquadron]

@archseer I'm sorry I got a bit confused in the commit message. The setting in question is hidden. If set to false, regardless of the setting of git-ignore or ignore, the .git directory entries show up in the file picker. The git-ignore setting does not guarantee that the .git directory is filtered out, only that the entries in the .gitignore files are. A workaround is to add .git to the .gitignore file, but that is a bit strange, since git itself does not require such an entry.

I'll adjust the commit message in the pull request to match this more clear explanation.

I've also considered the case in which the user wants to edit directly something in the .git folder, such as the .git/config file, and my answer to that is the :open command should suffice for such cases. I'm open to further discussion on it though.

Edit: Actually there's nothing wrong with my commit message or comment, it just wasn't as fleshed out. Leaving it for now unless you want me to adjust.