Fix Linux search issues (#13479)

In some rare cases, we wouldn't pick up .gitignore files in the right
order, causing performance issues for the project search and the file
finder

Release Notes:

- N/A

crates/worktree/src/ignore.rs

@@ -1,6 +1,7 @@
 use ignore::gitignore::Gitignore;
 use std::{ffi::OsStr, path::Path, sync::Arc};
 
+#[derive(Debug)]
 pub enum IgnoreStack {
     None,
     Some {