Support nested version control system files

[DanielNoord]

This was originally tried in #1134 but later reverted in #1249. See also discussion inhttps://github.com//issues/805

Basically, it would be good if .gitignore or other VCS ignore files that exist in subdirectories would also be respected.

[dyc3]

This is definitely related to #2228. This is also likely a problem for .editorconfig files too.

[gscalise]

Is there any reason in the TODO in here:

biome/crates/biome_fs/src/fs/os.rs

Lines 219 to 222 in b260d5b

	// TODO: remove in Biome 2.0, and directly use `.gitignore`
	/// Default list of ignored directories, in the future will be supplanted by
	/// detecting and parsing .ignore files
	const DEFAULT_IGNORE: &[&[u8]] = &[b".git", b".svn", b".hg", b".yarn", b"node_modules"];

to propose "directly using .gitignore" instead of relying on git2-rs and letting the library figure out what to ignore?

As far as I understand, there's a multitude of ways to ignore files in a git repository (.gitignore, nested .gitignore, entries in .git/info/exclude, global settings, user settings, etc). Trying to replicate git's behavior by only handling a subset of these cases -when it can be delegated to the library- doesn't seem too promising IMO.