Fix FS-related issues that were causing a test failure on linux (#13072)

This fixes `project_tests::rescan_and_remote_updates` .

That test was actually correctly failing, revealing two bugs on Linux.

Release Notes:

- Fixed an issue where file renames were not detected on Linux.
- Fixed performance problems caused by excessive file system events on
Linux.

---------

Co-authored-by: Mikayla <mikayla@zed.dev>

crates/project/src/project_tests.rs

@@ -2977,8 +2977,6 @@ async fn test_save_as(cx: &mut gpui::TestAppContext) {
     assert_eq!(opened_buffer, buffer);
 }
 
-// This test is currently disabled on Linux as it fails fails pretty consistently on that target.
-#[cfg(not(target_os = "linux"))]
 #[gpui::test(retries = 5)]
 async fn test_rescan_and_remote_updates(cx: &mut gpui::TestAppContext) {
     use worktree::WorktreeModelHandle as _;